H1 (critical): reorder send_support_message — get_or_create_thread now runs
AFTER a successful Telegram send, not before. Prod runs a single uvicorn
process with no --workers on a sync SQLAlchemy engine sharing one event
loop; holding a row-lock across the Telegram call (which can legally take
minutes on 429/5xx worker-grade retries) risked freezing the entire API on
a second concurrent request from the same user. send_message now also
accepts explicit timeout/max_retries so the interactive endpoint uses a
bounded budget instead of inheriting the long-polling worker's retry policy.
M1: web_support_messages and tg_support_messages both gain a support_chat_id
column (188 migration for the already-applied tg_support_messages table;
187 edited in place since it hasn't shipped yet). bridge._handle_group_reply
now resolves BOTH the Telegram and web candidate under the CURRENT
support_chat_id and refuses delivery loudly (logger.error) if both match,
instead of silently preferring the Telegram path — closing a cross-table
misroute risk that would surface if the support group is ever recreated.
M2: a media reply to a web-mirrored message (including photos with a
caption) is now refused in full with an explicit notice back in the topic,
instead of silently delivering just the caption text or logging a WARNING
nobody sees.
M3: list_support_messages/get_support_unread/mark_support_read switched
from async def to def — their bodies are pure sync psycopg calls; running
them as async def executed blocking DB work directly on the event loop.
M5: list_messages now takes a bounded LIMIT (last N, chronological) so a
long-lived thread doesn't return its entire history on every poll.
L1-L4: warn when Telegram doesn't return a message_id (routing dead-end),
rate limit is peeked before send and only recorded on success (failed
attempts no longer burn the budget), SlidingWindowLimiter gained the same
empty-bucket cleanup as RateLimitMiddleware, and _require_username now
strips whitespace so a proxy-injected space can't fork a second thread.
L5: removed 187 from _manifest_applied.txt — the deploy pipeline tracks
applied migrations via _schema_migrations, not this file, and keeping an
unmerged migration name out of it preserves the option to rename before
merge without tripping the "can't rename applied migrations" test.