feat(mcpd): ResourceRevision + ResourceProposal services + Prompt revision integration

Phase 2 of the Skills + Revisions + Proposals work. Stands up the generic
revision/proposal layer and wires Prompt into it. Skills will plug into the
same infrastructure in PR-3 with no further service changes required.

This PR is intentionally additive: PromptRequest table and routes are
unchanged. The /api/v1/proposals API runs side-by-side with the legacy
/api/v1/promptrequests API. The PromptRequest cutover (rename + backfill +
mcplocal rewire) is deferred to a later PR so this one stays reviewable.

## What's added

### Repositories (src/mcpd/src/repositories/)
- resource-revision.repository.ts — append-only revision log keyed by
  (resourceType, resourceId). Soft FK; no relations declared. Supports
  history listing, semver lookup, and contentHash cross-resource search.
- resource-proposal.repository.ts — generic propose queue. Status lifecycle
  pending → approved | rejected. Mirrors Prompt's `?? ''` workaround for
  nullable-FK compound lookups.

### Services (src/mcpd/src/services/)
- resource-revision.service.ts — record() inserts a revision with a stable
  sha256 contentHash computed from canonicalised JSON (key-sorted at every
  level so reordered objects produce the same hash). Caller passes a
  pre-computed semver; service does NOT decide bump policy.
- resource-proposal.service.ts — propose / approve / reject / list, with a
  per-resourceType handler registry. PromptService registers the 'prompt'
  handler at construction; the SkillService will register 'skill' in PR-3.
  approve() runs in a Prisma $transaction so the resource update + revision
  insert + proposal status flip are atomic.

### Pure utility (src/mcpd/src/utils/semver.ts)
- bumpSemver(current, kind) for major / minor / patch
- compareSemver(a, b) — numeric, not lex (10 > 9)
- isValidSemver(s)
- Invalid input falls back to '0.1.0' rather than throwing — keeps the
  audit-write path from blowing up the prompt update if a row's semver
  ever drifts out of MAJOR.MINOR.PATCH shape.

### Routes (src/mcpd/src/routes/)
- revisions.ts — GET /api/v1/revisions?resourceType=&resourceId=,
  GET /api/v1/revisions/:id, GET /api/v1/revisions/:id/diff?against=<id|live>
  (unified-format diff via the `diff` package), and POST
  /api/v1/prompts/:id/restore-revision { revisionId, note? }.
- proposals.ts — GET / POST /api/v1/proposals,
  GET /api/v1/proposals/:id, PUT for body updates, POST .../approve and
  POST .../reject, plus DELETE.

## What's changed

- PromptService.create / update now record a ResourceRevision when the
  revision service is wired. Update auto-bumps patch on content change;
  authors can override via `--bump major|minor|patch` or `--semver X.Y.Z`
  on the CLI (forwarded into the PUT body). Best-effort: revision write
  failures are swallowed so the prompt save still succeeds (revision is
  audit, not source of truth).
- PromptService.setProposalService registers a 'prompt' approval handler
  with the proposal service. Approval runs in a Prisma transaction:
  upsert prompt → record revision → update currentRevisionId → flip
  proposal status. semver bumps to 0.1.0 on first approval, patch
  thereafter.
- New CLI flags on `mcpctl edit prompt`: --bump, --semver, --note. They're
  prompt-only (validated client-side); other resources reject them.
- Aliases in shared.ts: `proposal`/`prop` → proposals,
  `revision`/`rev` → revisions.
- diff dependency added to mcpd.

## Tests

- src/mcpd/tests/utils/semver.test.ts — covers bump/compare/validate
  including numeric (not lex) semver compare and invalid-input fallback.
- prompt-service.test.ts updated: makePrompt fixture now sets semver +
  agentId + currentRevisionId; updatePrompt assertion expects the
  auto-bumped patch in the same update call.
- prompt-routes.test.ts updated symmetrically.

## RBAC

`proposals` and `revisions` URL segments map to the existing `prompts`
permission for now. PR-7 may split if a "reviewer" role becomes useful.

## Verification

Full suite: 158 test files / 2127 tests green.
`pnpm build` clean across all 6 workspace packages.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/mcpd/tests/services/prompt-service.test.ts

@@ -11,10 +11,13 @@ function makePrompt(overrides: Partial<Prompt> = {}): Prompt {
     name: 'test-prompt',
     content: 'Hello world',
     projectId: null,
+    agentId: null,
     priority: 5,
     summary: null,
     chapters: null,
     linkTarget: null,
+    semver: '0.1.0',
+    currentRevisionId: null,
     version: 1,
     createdAt: new Date(),
     updatedAt: new Date(),
@@ -175,7 +178,9 @@ describe('PromptService', () => {
     it('should update prompt content', async () => {
       vi.mocked(promptRepo.findById).mockResolvedValue(makePrompt());
       await service.updatePrompt('prompt-1', { content: 'updated' });
-      expect(promptRepo.update).toHaveBeenCalledWith('prompt-1', { content: 'updated' });
+      // Auto-patch bump on content change (PR-2): updatePrompt now also
+      // emits the new semver in the same update call.
+      expect(promptRepo.update).toHaveBeenCalledWith('prompt-1', { content: 'updated', semver: '0.1.1' });
     });
 
     it('should throw for missing prompt', async () => {