feat(skill): comprehensive grind rewrite and cross-skill integration (#896)

* refactor: adopt dead helpers across codebase

Wire up extracted helpers from Titan runs that existed but were never
consumed, reducing boilerplate and improving error specificity.

- Adopt named_child_text across 27 sites in 11 Rust extractors
- Migrate cpp.rs from hand-rolled find_cpp_parent_class to find_enclosing_type_name
- Add toSymbolRef helper in shared/normalize.ts, adopt at 15 mapping sites
- Wire ParseError in parser.ts for structured PARSE_FAILED error codes
- Wire BoundaryError in boundaries.ts to distinguish config/DB failures from clean results
- Add --modules/--threshold flags to codegraph structure command
- Wire batchQuery in CLI batch command, removing duplicated routing logic
- Route detect-changes pending analysis through unified runAnalyses engine

* fix: address review feedback on dead helper adoption (#895)

- manifesto.ts: report 'warn' instead of 'pass' when boundary check throws
- structure.ts: validate --threshold flag rejects non-numeric input
- dependencies.ts: clarify intentional skip of toSymbolRef for callers

* feat(skill): add /titan-grind phase and wire into /titan-run pipeline

Forge extracts helpers but never completes the adoption loop — dead
symbol count inflates with every run. Grind closes the gap by finding
dead helpers from forge, classifying them (adopt/re-export/promote/
false-positive/remove), wiring them into consumers, and gating on a
non-positive dead-symbol delta.

Pipeline is now: recon → gauntlet → sync → forge → grind → close

* fix(skill): add resilience and codegraph usage to /titan-grind

- Track currentTarget, processedTargets, failedTargets in state for
  mid-run resume after interruption
- Persist grind classifications to grind-targets.ndjson (append-only)
  so re-runs skip already-analyzed targets
- Write titan-state.json after every target, not just at phase end
- Add interrupted-mid-target recovery logic in edge cases
- Use codegraph audit/context/fn-impact/where/query/ast before edits
- Add codegraph diff-impact --staged before commits
- Add codegraph build after edits to keep graph current
- Add --target flag for retrying individual failures

* feat(skill): comprehensive grind rewrite and cross-skill integration

Rewrite titan-grind with full resilience (state machine, .bak files,
NDJSON persistence, snapshot management), codegraph integration
(audit/context/fn-impact/diff-impact), diff review (DR1-DR3), drift
detection, false positive tracking via issues.ndjson, and phase
timestamps.

Update titan-close: grind-targets.ndjson in artifact load list,
adoption concern type in PR grouping, grind metrics in before/after
comparison, GRIND row in Pipeline Timeline, Grind Results section
in report template, grind block in close-summary.json.

Update titan-reset: titan-grind-baseline snapshot deletion and
grind-targets.ndjson in artifact listing.

* fix(skill): align titan-close grind metrics with titan-grind NDJSON schema (#896)

titan-close was reading status/deadBefore/deadAfter fields that
titan-grind never writes. Updated to read classification field from
grind-targets.ndjson and pull metrics from titan-state.json grind block.

* fix: restore null guard in batchQuery multi-batch detection (#896)

typeof null === 'object' is true in JS, so accessing .command on null
would throw TypeError. Added explicit null check before the typeof.

* fix(skill): add --start-from grind pre-checks row to titan-run (#896)

Without a validation table row for grind, the orchestrator had no
guidance on which pre-checks to run when starting directly from grind.

Author: carlos-alm

.claude/skills/titan-close/SKILL.md

@@ -65,6 +65,7 @@ Your goal: analyze all commits on the current branch, split them into focused PR
    - `.codegraph/titan/issues.ndjson` — issue tracker from all phases
    - `.codegraph/titan/arch-snapshot.json` — pre-forge architectural snapshot (communities, structure, drift). Use for before/after comparison in the Metrics section. May not exist if capture failed.
    - `.codegraph/titan/drift-report.json` — cumulative drift reports from all phases. May not exist if no drift was detected.
+   - `.codegraph/titan/grind-targets.ndjson` — grind phase adoption targets and outcomes. Each line: `{target, file, phase, classification, reason, consumers, pattern, timestamp}`. May not exist if grind wasn't run.
 
    If `titan-state.json` is missing after the search, stop: "No Titan session found. Run `/titan-recon` first."
 
@@ -146,6 +147,9 @@ Use `sync.json` execution phases as the primary guide if available:
    - Group by domain: `fix: address quality issues in <domain>`
 6. **Warning improvements** — commits addressing warn-level issues
    - Group by domain: `refactor: improve code quality in <domain>`
+7. **Helper adoption** — commits from grind phase adopting dead helpers into callsites
+   - PR title: `refactor: adopt dead helpers in <domain>`
+   - Look for `grind(...)` commit prefixes or commits touching files listed in `grind-targets.ndjson`
 
 ### Fallback grouping (if no sync.json)
 
@@ -164,7 +168,7 @@ Record the grouping plan:
   {
     "pr": 1,
     "title": "...",
-    "concern": "dead_code|abstraction|cycle_break|decomposition|quality_fix|warning",
+    "concern": "dead_code|abstraction|cycle_break|decomposition|quality_fix|warning|adoption",
     "domain": "<domain name>",
     "commits": ["<sha1>", "<sha2>"],
     "files": ["<file1>", "<file2>"],
@@ -202,6 +206,17 @@ codegraph complexity --health --sort mi -T --json --limit 10
 
 If `.codegraph/titan/arch-snapshot.json` was captured before forge, compare its `structure` data against current `codegraph structure --depth 2 --json` output. Report cohesion changes per directory (improved / degraded / unchanged). Include in the "Metrics: Before & After" section of the report.
 
+### Grind metrics (if grind-targets.ndjson exists)
+
+If `.codegraph/titan/grind-targets.ndjson` exists, parse it and cross-reference with `titan-state.json → grind`:
+- **Targets processed:** count entries in `grind.processedTargets` (from titan-state.json)
+- **Targets failed:** count entries in `grind.failedTargets` (from titan-state.json)
+- **False positives identified:** count entries with `classification: "false-positive"` in grind-targets.ndjson (or from `grind.falsePositives` in titan-state.json)
+- **Adopted:** count entries with `classification: "adopt"` in grind-targets.ndjson
+- **Dead symbol delta:** from `grind.deadSymbolDelta` in titan-state.json (or compute from baseline vs final dead symbol counts)
+
+Include these in the Metrics: Before & After section and the Grind Results report section.
+
 ### Compute deltas
 
 Compare final metrics against `titan-state.json` baseline:
@@ -342,7 +357,8 @@ Read `titan-state.json → phaseTimestamps` for real wall-clock data. If `phaseT
 | GAUNTLET | <computed from phaseTimestamps.gauntlet> | <iterations count if resuming> |
 | SYNC | <computed from phaseTimestamps.sync> | — |
 | FORGE | <computed from phaseTimestamps.forge> | <commit count>, first at <time>, last at <time> |
-| GATE | across forge | <total runs> inline with forge commits |
+| GRIND | <computed from phaseTimestamps.grind> | <targets processed>, <adoptions made> |
+| GATE | across forge/grind | <total runs> inline with forge/grind commits |
 | CLOSE | <computed from phaseTimestamps.close> | — |
 | **Total** | <sum of all phases> | — |
 
@@ -393,6 +409,22 @@ Read `titan-state.json → phaseTimestamps` for real wall-clock data. If `phaseT
 
 ---
 
+## Grind Results (if grind ran)
+
+**Targets processed:** <N> | **Adopted:** <N> | **Failed:** <N> | **False positives:** <N>
+
+### Adoption Summary
+
+<Table: target name, dead symbols before, dead symbols after, delta, files modified>
+
+### False Positives Logged
+
+<Table: target name, reason (dynamic import / re-export / closure-local / type noise), logged to issues.ndjson>
+
+> Omit this section entirely if `grind-targets.ndjson` does not exist.
+
+---
+
 ## Changes Made
 
 ### Commits: <total count>
@@ -551,6 +583,7 @@ Write `.codegraph/titan/close-summary.json`:
   },
   "audit": { "totalAudited": 0, "pass": 0, "warn": 0, "fail": 0, "decompose": 0 },
   "gate": { "totalRuns": 0, "pass": 0, "warn": 0, "fail": 0, "rollbacks": 0 },
+  "grind": { "targetsProcessed": 0, "adopted": 0, "failed": 0, "falsePositives": 0, "deadSymbolDelta": 0 },
   "issues": { "codegraph": 0, "tooling": 0, "process": 0, "codebase": 0 },
   "prs": [
     { "number": 0, "url": "<url>", "title": "<title>", "concern": "<type>", "domain": "<domain>", "commits": 0 }