refactor: update ClaudeMdForCaller comment and add copilot instructions

Signed-off-by: ersan bilik <ersanbilik@gmail.com>

Author: bilersan

.github/copilot-instructions.md

@@ -0,0 +1,106 @@
+# Project Context
+
+<!-- ctx:copilot -->
+<!-- DO NOT REMOVE: This marker indicates ctx-managed content -->
+
+## Context System
+
+This project uses Context (`ctx`) for persistent AI context
+management. Your memory is NOT ephemeral — it lives in `.context/` files.
+
+## On Session Start
+
+Read these files **in order** before starting any work:
+
+1. `.context/CONSTITUTION.md` — Hard rules, NEVER violate
+2. `.context/TASKS.md` — Current work items
+3. `.context/CONVENTIONS.md` — Code patterns and standards
+4. `.context/ARCHITECTURE.md` — System structure
+5. `.context/DECISIONS.md` — Architectural decisions with rationale
+6. `.context/LEARNINGS.md` — Gotchas, tips, lessons learned
+7. `.context/GLOSSARY.md` — Domain terms and abbreviations
+8. `.context/AGENT_PLAYBOOK.md` — How to use this context system
+
+After reading, confirm: "I have read the required context files and I'm
+following project conventions."
+
+## When Asked "Do You Remember?"
+
+**Do this FIRST (silently):**
+- Read `.context/TASKS.md`
+- Read `.context/DECISIONS.md` and `.context/LEARNINGS.md`
+- Check `.context/sessions/` for recent session files
+
+**Then respond with a structured readback:**
+1. **Last session**: cite the most recent session topic and date
+2. **Active work**: list pending or in-progress tasks
+3. **Recent context**: mention 1-2 recent decisions or learnings
+4. **Next step**: offer to continue or ask what to focus on
+
+**Never** lead with "I don't have memory." The `.context/` files are
+your memory. Read them silently, then present what you found as recall.
+
+## Session Persistence
+
+After completing meaningful work, save a session summary to
+`.context/sessions/`.
+
+### Session File Format
+
+Create a file named `YYYY-MM-DD-topic.md`:
+
+```markdown
+# Session: YYYY-MM-DD — Brief Topic Description
+
+## What Was Done
+- Describe completed work items
+
+## Decisions
+- Key decisions made and their rationale
+
+## Learnings
+- Gotchas, tips, or insights discovered
+
+## Next Steps
+- Follow-up work or remaining items
+```
+
+### When to Save
+
+- After completing a task or feature
+- After making architectural decisions
+- After a debugging session
+- Before ending the session
+- At natural breakpoints in long sessions
+
+## Context Updates During Work
+
+Proactively update context files as you work:
+
+| Event                       | Action                              |
+|-----------------------------|-------------------------------------|
+| Made architectural decision | Add to `.context/DECISIONS.md`  |
+| Discovered gotcha/bug       | Add to `.context/LEARNINGS.md`  |
+| Established new pattern     | Add to `.context/CONVENTIONS.md` |
+| Completed task              | Mark [x] in `.context/TASKS.md` |
+
+## Self-Check
+
+Periodically ask yourself:
+
+> "If this session ended right now, would the next session know what happened?"
+
+If no — save a session file or update context files before continuing.
+
+## CLI Commands
+
+If `ctx` is installed, use these commands:
+
+```bash
+ctx status        # Context summary and health check
+ctx agent         # AI-ready context packet
+ctx drift         # Check for stale context
+ctx recall list   # Recent session history
+```
+
+<!-- ctx:copilot:end -->

internal/assets/embed.go

@@ -251,8 +251,8 @@ func ClaudeMd() ([]byte, error) {
 	return FS.ReadFile("claude/CLAUDE.md")
 }
 
-// ClaudeMdForCaller reads a caller-specific CLAUDE.md override if available,
-// falling back to the default claude/CLAUDE.md template.
+// ClaudeMdForCaller reads the CLAUDE.md template, using a caller-specific override if available.
+// Falls back to the default CLAUDE.md when no override exists for the caller.
 func ClaudeMdForCaller(caller string) ([]byte, error) {
 	if caller != "" {
 		override, err := FS.ReadFile("overrides/" + caller + "/CLAUDE.md")