feat: replace pr_review with spec-driven CI gates and pr-review skill

Add validate_spec, check_pr_size, fast_molecule, nightly_gate, and
create_dependency_pr CI modules. Remove the monolithic pr_review module
and its tests. Replace pr_review CI steps with validate_spec + check_pr_size
+ curl-based APPROVE. Add spec-driven-development and pr-review skills.
Remove dead get_reviewer_token. Update translations and AGENTS.md.

Closes DEVX-155

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

.devin/skills/spec-driven-development/SKILL.md

@@ -0,0 +1,130 @@
+# Spec-Driven Development
+
+## Overview
+
+Every change starts with a spec. No spec, no code. No code, no PR.
+
+The spec is a markdown file at `docs/specs/<TASK-ID>.md` in the repo.
+It contains structured requirements (REQ-IDs) and acceptance criteria
+(AC checklist) that CI validates before merge.
+
+## Workflow
+
+1. **Create Vikunja task** — `make create-task -- --title "Title" --description "..."`
+2. **Write spec** — Create `docs/specs/<TASK-ID>.md` (see template below)
+3. **Create branch** — `git checkout -b <PREFIX>-N-short-description`
+4. **Implement** — Write code with `# Implements: REQ-N` comments
+5. **Check ACs** — Tick all acceptance criteria checkboxes in the spec
+6. **Push and create PR** — `make push-with-pr`
+7. **CI validates** — Spec validation, PR size check, fast molecule, lint, tests
+8. **Auto-merge** — Add `ready-to-merge` label after review
+9. **Auto-deploy** — Post-merge deploys to staging (if nightly gate is green)
+
+## Spec Template
+
+```markdown
+# <TASK-ID>: <Title>
+
+## Problem
+<What is broken or missing? Why does this change exist?>
+
+## Approach
+<How will you solve it? What are the key design decisions?>
+
+REQ-1: <First requirement description>
+REQ-2: <Second requirement description>
+REQ-3: <Third requirement description>
+
+## Test Plan
+- <How will you verify each REQ is implemented correctly?>
+- <Include unit tests, molecule scenarios, integration tests>
+
+## Deploy Plan
+- <How will this change be deployed?>
+- <What order do components need to deploy in?>
+- <Are there migrations or one-time operations?>
+
+## Rollback Plan
+- <How do you revert if something goes wrong?>
+- <What data/state changes are irreversible?>
+
+## Acceptance Criteria
+- [ ] REQ-1: <criterion that proves REQ-1 is done>
+- [ ] REQ-2: <criterion that proves REQ-2 is done>
+- [ ] REQ-3: <criterion that proves REQ-3 is done>
+```
+
+## CI Validation
+
+The `devx.ci.validate_spec` module checks:
+
+1. **Spec file exists** at `docs/specs/<TASK-ID>.md` (TASK-ID from branch name)
+2. **Required sections present**: Problem, Approach, Test Plan, Deploy Plan, Rollback Plan, Acceptance Criteria
+3. **At least one REQ-ID** line (format: `REQ-N: <description>`)
+4. **All AC checkboxes checked** (`- [x]`, not `- [ ]`)
+
+If any check fails, CI blocks the PR before expensive jobs run.
+
+## PR Size Limits
+
+CI enforces max 500 lines / 10 files changed (excluding CHANGELOG.md,
+README.md, badges, lock files). Oversized PRs are rejected. Split your
+work into smaller PRs.
+
+## Code-to-Spec Linking
+
+Each function, task, or template that implements a requirement should
+have a comment:
+
+```python
+# Implements: REQ-1
+def install_sso_bridge():
+    ...
+```
+
+```yaml
+# Implements: REQ-2
+- name: Clone infra repo
+  git:
+    ...
+```
+
+## Fast Molecule (Pre-merge)
+
+CI runs molecule only for **changed roles** (detected via git diff),
+with converge + verify only, single platform. This gives quick feedback
+(~5-10 min) without the full molecule suite.
+
+## Full Molecule (Nightly)
+
+The complete molecule suite (all scenarios, all platforms) runs nightly
+at 02:00 CET on master. If it fails:
+- A Gitea issue is created with the `feedback` label
+- The `NIGHTLY_STATUS` repo variable is set to `failed:<run_id>`
+- All staging deploys are blocked until nightly passes again
+
+## Auto-Deploy on Merge
+
+Every merged PR auto-deploys to staging (if nightly gate is green).
+No manual trigger needed. The deploy runs the full pipeline:
+provision → deploy-observability → deploy-customer → configure-oidc.
+
+For grm/sso-bridge: post-merge publishes the package, then auto-creates
+an infra PR to bump the pinned version. That infra PR auto-deploys when
+merged.
+
+## Key Commands
+
+```bash
+# Validate spec locally (before pushing)
+python -m devx.ci.validate_spec --branch <PREFIX>-N-description
+
+# Check PR size locally
+python -m devx.ci.check_pr_size --base origin/master --head HEAD
+
+# See which roles need fast molecule
+python -m devx.ci.fast_molecule --base origin/master --head HEAD
+
+# Check nightly gate status
+python -m devx.ci.nightly_gate --repo oblachno/infra --action check
+```