D-011 freezes the regex_extract Jinja filter signature
`regex_extract(text, pattern, *, group=1, name=None)`, google-re2 engine,
raise on no-match — unblocks backend B0.5 templating sandbox.
D-012 splits storage in two pools: `blobs/` (CAS sha256 + gzip) for C2
binary outputs and `evidence/` (flat per engagement) for user uploads,
10 MB per-blob cap, no global quota v1.
Q-001 and Q-002 removed from open-questions.md (resolved).
Q-003/Q-004/Q-005 marked `deferred` with explicit re-open conditions.
Captures the four grey areas team-lead flagged in the sprint 0 brief
(regex_extract semantics, output_blob_ref storage, /hosts/sync merge
behaviour, payload_type↔home-C2 mapping) plus stale-host policy.
No decisions taken: each entry lists options, a recommended default
if no decision is reached, and a "becomes blocking when…" trigger.
Resolved questions will move to spec-decisions.md as D-NNN entries.
