docs: move the LOTUS_TODO / LOTUS_TESTING backlogs into Gitea issues; keep a reference-only LOTUS_REFERENCE.md

LOTUS_TODO.md → LOTUS_REFERENCE.md (design laws, decided deferrals,
server-blocked features, operational reference only). Every open task was
filed: cinny #195–#210, cinny-desktop #15–#18, matrix #8–#10.

LOTUS_TESTING.md keeps the automated-coverage map, the Playwright notes and
the deploy tip; every manual checklist is now a `qa` issue under the
'Manual QA backlog' (cinny #170–#194, #198) and 'Desktop QA backlog'
(cinny-desktop #11–#14, #18) milestones.

Repointed the README, LOTUS_FEATURES, CI and source comments that
referenced LOTUS_TODO.md.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPmy3tPq869XDW4njjVaKA

README.md

@@ -174,7 +174,7 @@ Beyond the web client, the desktop app adds native OS integration (Windows-focus
 
 The source code lives in `/root/code/cinny`. All changes should be made on the `lotus` branch. Push to `origin/lotus` and CI will automatically build and deploy to [chat.lotusguild.org](https://chat.lotusguild.org) in approximately 11 minutes — no manual build or deploy steps required.
 
-See [LOTUS_FEATURES.md](LOTUS_FEATURES.md) for the full feature changelog and [LOTUS_TODO.md](LOTUS_TODO.md) for the work backlog.
+See [LOTUS_FEATURES.md](LOTUS_FEATURES.md) for the full feature changelog and [LOTUS_REFERENCE.md](LOTUS_REFERENCE.md) for the design laws and operational reference (open work is in [Gitea issues](https://code.lotusguild.org/LotusGuild/cinny/issues)).
 
 ### Local Development
 
@@ -209,7 +209,7 @@ avatar decorations on EC video tiles, and a native transparent background.
 (`io.lotus.set_quality`).
 
 The fork's `io.lotus.*` action catalog + the publish procedure are in
-**[`LOTUS_TODO.md`](LOTUS_TODO.md)** ("Element Call fork — operational reference");
+**[`LOTUS_REFERENCE.md`](LOTUS_REFERENCE.md)** ("Element Call fork — operational reference");
 infra/hosting + build-pipeline notes live in the `LotusGuild/matrix` repo README.
 Search the docs for the **`[EC-FORK]`** tag to find every related note.