feat(connectors): add dynamic selectors to knowledge base connector config

Replace manual ID text inputs with dynamic selector dropdowns that fetch
options from the existing selector registry. Users can toggle between
selector and manual input via canonical pairs (basic/advanced mode).

Adds selector support to 12 connectors: Airtable (cascading base→table),
Slack, Gmail, Google Calendar, Linear (cascading team→project), Jira,
Confluence, MS Teams (cascading team→channel), Notion, Asana, Webflow,
and Outlook. Dependency clearing propagates across canonical siblings to
prevent stale cross-mode data on submit.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: waleedlatif1

.claude/commands/add-connector.md

@@ -117,6 +117,8 @@ export const {service}Connector: ConnectorConfig = {
 
 The add-connector modal renders these automatically — no custom UI needed.
 
+Three field types are supported: `short-input`, `dropdown`, and `selector`.
+
 ```typescript
 // Text input
 {
@@ -141,6 +143,136 @@ The add-connector modal renders these automatically — no custom UI needed.
 }
 ```
 
+## Dynamic Selectors (Canonical Pairs)
+
+Use `type: 'selector'` to fetch options dynamically from the existing selector registry (`hooks/selectors/registry.ts`). Selectors are always paired with a manual fallback input using the **canonical pair** pattern — a `selector` field (basic mode) and a `short-input` field (advanced mode) linked by `canonicalParamId`.
+
+The user sees a toggle button (ArrowLeftRight) to switch between the selector dropdown and manual text input. On submit, the modal resolves each canonical pair to the active mode's value, keyed by `canonicalParamId`.
+
+### Rules
+
+1. **Every selector field MUST have a canonical pair** — a corresponding `short-input` (or `dropdown`) field with the same `canonicalParamId` and `mode: 'advanced'`.
+2. **`required` must be set identically on both fields** in a pair. If the selector is required, the manual input must also be required.
+3. **`canonicalParamId` must match the key the connector expects in `sourceConfig`** (e.g. `baseId`, `channel`, `teamId`). The advanced field's `id` should typically match `canonicalParamId`.
+4. **`dependsOn` references the selector field's `id`**, not the `canonicalParamId`. The modal propagates dependency clearing across canonical siblings automatically — changing either field in a parent pair clears dependent children.
+
+### Selector canonical pair example (Airtable base → table cascade)
+
+```typescript
+configFields: [
+  // Base: selector (basic) + manual (advanced)
+  {
+    id: 'baseSelector',
+    title: 'Base',
+    type: 'selector',
+    selectorKey: 'airtable.bases',     // Must exist in hooks/selectors/registry.ts
+    canonicalParamId: 'baseId',
+    mode: 'basic',
+    placeholder: 'Select a base',
+    required: true,
+  },
+  {
+    id: 'baseId',
+    title: 'Base ID',
+    type: 'short-input',
+    canonicalParamId: 'baseId',
+    mode: 'advanced',
+    placeholder: 'e.g. appXXXXXXXXXXXXXX',
+    required: true,
+  },
+  // Table: selector depends on base (basic) + manual (advanced)
+  {
+    id: 'tableSelector',
+    title: 'Table',
+    type: 'selector',
+    selectorKey: 'airtable.tables',
+    canonicalParamId: 'tableIdOrName',
+    mode: 'basic',
+    dependsOn: ['baseSelector'],       // References the selector field ID
+    placeholder: 'Select a table',
+    required: true,
+  },
+  {
+    id: 'tableIdOrName',
+    title: 'Table Name or ID',
+    type: 'short-input',
+    canonicalParamId: 'tableIdOrName',
+    mode: 'advanced',
+    placeholder: 'e.g. Tasks',
+    required: true,
+  },
+  // Non-selector fields stay as-is
+  { id: 'maxRecords', title: 'Max Records', type: 'short-input', ... },
+]
+```
+
+### Selector with domain dependency (Jira/Confluence pattern)
+
+When a selector depends on a plain `short-input` field (no canonical pair), `dependsOn` references that field's `id` directly. The `domain` field's value maps to `SelectorContext.domain` automatically via `SELECTOR_CONTEXT_FIELDS`.
+
+```typescript
+configFields: [
+  {
+    id: 'domain',
+    title: 'Jira Domain',
+    type: 'short-input',
+    placeholder: 'yoursite.atlassian.net',
+    required: true,
+  },
+  {
+    id: 'projectSelector',
+    title: 'Project',
+    type: 'selector',
+    selectorKey: 'jira.projects',
+    canonicalParamId: 'projectKey',
+    mode: 'basic',
+    dependsOn: ['domain'],
+    placeholder: 'Select a project',
+    required: true,
+  },
+  {
+    id: 'projectKey',
+    title: 'Project Key',
+    type: 'short-input',
+    canonicalParamId: 'projectKey',
+    mode: 'advanced',
+    placeholder: 'e.g. ENG, PROJ',
+    required: true,
+  },
+]
+```
+
+### How `dependsOn` maps to `SelectorContext`
+
+The connector selector field builds a `SelectorContext` from dependency values. For the mapping to work, each dependency's `canonicalParamId` (or field `id` for non-canonical fields) must exist in `SELECTOR_CONTEXT_FIELDS` (`lib/workflows/subblocks/context.ts`):
+
+```
+oauthCredential, domain, teamId, projectId, knowledgeBaseId, planId,
+siteId, collectionId, spreadsheetId, fileId, baseId, datasetId, serviceDeskId
+```
+
+### Available selector keys
+
+Check `hooks/selectors/types.ts` for the full `SelectorKey` union. Common ones for connectors:
+
+| SelectorKey | Context Deps | Returns |
+|-------------|-------------|---------|
+| `airtable.bases` | credential | Base ID + name |
+| `airtable.tables` | credential, `baseId` | Table ID + name |
+| `slack.channels` | credential | Channel ID + name |
+| `gmail.labels` | credential | Label ID + name |
+| `google.calendar` | credential | Calendar ID + name |
+| `linear.teams` | credential | Team ID + name |
+| `linear.projects` | credential, `teamId` | Project ID + name |
+| `jira.projects` | credential, `domain` | Project key + name |
+| `confluence.spaces` | credential, `domain` | Space key + name |
+| `notion.databases` | credential | Database ID + name |
+| `asana.workspaces` | credential | Workspace GID + name |
+| `microsoft.teams` | credential | Team ID + name |
+| `microsoft.channels` | credential, `teamId` | Channel ID + name |
+| `webflow.sites` | credential | Site ID + name |
+| `outlook.folders` | credential | Folder ID + name |
+
 ## ExternalDocument Shape
 
 Every document returned from `listDocuments`/`getDocument` must include:
@@ -287,6 +419,12 @@ export const CONNECTOR_REGISTRY: ConnectorRegistry = {
 - [ ] **Auth configured correctly:**
   - OAuth: `auth.provider` matches an existing `OAuthService` in `lib/oauth/types.ts`
   - API key: `auth.label` and `auth.placeholder` set appropriately
+- [ ] **Selector fields configured correctly (if applicable):**
+  - Every `type: 'selector'` field has a canonical pair (`short-input` or `dropdown` with same `canonicalParamId` and `mode: 'advanced'`)
+  - `required` is identical on both fields in each canonical pair
+  - `selectorKey` exists in `hooks/selectors/registry.ts`
+  - `dependsOn` references selector field IDs (not `canonicalParamId`)
+  - Dependency `canonicalParamId` values exist in `SELECTOR_CONTEXT_FIELDS`
 - [ ] `listDocuments` handles pagination and computes content hashes
 - [ ] `sourceUrl` set on each ExternalDocument (full URL, not relative)
 - [ ] `metadata` includes source-specific data for tag mapping