Add Gitea Actions CI + switch to PR-based workflow

- Add .gitea/workflows/ci.yml: typecheck -> lint -> unit -> build -> deterministic
  Playwright e2e against the dev webServer (LLM_STUB=1). No dind/docker/static IP.
- package-lock.json is committed (reproducible `npm ci`); verified npm install is a no-op.
- Add CHANGELOG.md, set version 0.1.0, add .env (gitignored) + .env.example placeholder.
- Document the mandatory feature-branch -> PR -> CI -> auto-merge workflow in
  AGENTS.md + README.md (e2e now runs in CI on every PR).
- Add Playwright html/json reporters (playwright-report/, test-results/e2e.json)
  for the CI E2E-results summary step and the failure artifact upload.

CHANGELOG.md

@@ -0,0 +1,11 @@
+# Changelog
+
+All notable changes to **History** are listed here, newest first.
+
+## v0.1.0 — 2026-10-11 08:02
+
+- Added a Gitea Actions CI pipeline (`.gitea/workflows/ci.yml`: `typecheck → lint → unit → build → deterministic Playwright e2e`). E2e runs against the app's own dev webServer (`LLM_STUB=1`) — no dind/docker.
+- Committed `package-lock.json` so CI uses a reproducible `npm ci`.
+- Switched to the mandatory PR-based workflow: feature branch → PR to `master` → CI green → auto-merge → tag + manual deploy (documented in `AGENTS.md`).
+- Versioned the repo at `0.1.0` (`package.json`) and added `CHANGELOG.md`, `.env` (gitignored) and `.env.example`.
+- This change is the first one landed through the new PR process (dogfooding it).