Add Matrix intake bot (M1+M2): typed message → approved fundraising-grid write

New backend/matrix_intake/ runs as its own process (matrix-nio isolated from the
stdlib CRM): local-Qwen parse via Spark Control → in-thread human approval
(yes/edit/no) → write through the CRM's own log-communication endpoint, tagged
source=matrix_intake. Adds read-only GET /api/intake/match (returns grid row id,
no-duplicate contract); threads provenance through handle_log_fundraising_communication.
Reviewer-passed: pop-before-commit closes a double-approve race; edit-grammar fix.
Text-only v1; business-card photo (M3) deferred (no Spark vision model).
26/26 tests green; live Matrix smoke pending deploy.

backend/matrix_intake/requirements.txt

@@ -0,0 +1,4 @@
+# Matrix intake bot — isolated to this component's own process. matrix-nio is the ONLY
+# third-party runtime dep and MUST NOT be added to the stdlib CRM (backend/server.py).
+# The Spark/Qwen + CRM-API calls reuse the repo's stdlib HTTP client (backend/ingest/http_util).
+matrix-nio>=0.24