feat(plane): memory store (file and MinIO) and the remember task (harnessx-removal task 2)

plane/memory.py: the MemoryStore interface with FileStore (index.jsonl, facts by
content hash, repos/<host>__<owner>__<name>/<pin>.jsonl, idempotent ingest,
deterministic row ids, refusal below 1 GiB free naming the path) and MinioStore
(object metadata and tags, S3 Select pushdown probed once per process with a
logged local fallback, object version ids on every row read, versioning and
runs/ lifecycle helper, presigned URLs). OUSAST_MEMORY selects the backend;
MINIO_* settings come from .env; the minio SDK is the optional extra `minio`.

plane/tasks/remember.py: model-free rows (facts, verdict, unit_cost, alert)
from a case's artifacts; remember_run computes them on the host for a recorded
run without writing into it. reconciler.mark_done (477 lines total), seed
before and ingest after `ousast plane run`, `ousast plane remember <run>`.
The generator annotates each repo-facts Task with openultrasast.io/memory-key
(repo, pin, candidates digest, image digest) and the Run with its population
and split; plane/ regenerated.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01EmM1j46qgKMh3zqD1QMwEo

pyproject.toml

@@ -20,6 +20,11 @@ dependencies = ["pyyaml>=6.0"]
 harnessx = [
     "harnessx @ git+https://github.com/Darwin-Agent/HarnessX.git@274c512eea67c64701f992d3b6fe06f0fd590ef0",
 ]
+# The plane's memory store on MinIO (OUSAST_MEMORY=minio://<bucket>, plane/memory.py). Imported lazily; the
+# core install and the file store need nothing beyond PyYAML.
+minio = [
+    "minio>=7.2,<8",
+]
 # Structured parse for overlay (JS/C/C++/Java/Python). Core install stays empty.
 # Wheels are MIT; import is lazy via openultrasast.semantic.extra.
 semantic = [
@@ -74,6 +79,11 @@ ignore_missing_imports = true
 module = "tree_sitter"
 ignore_missing_imports = true
 
+# The minio SDK is an optional extra, absent in the type-check environment (plane/memory.py imports it lazily).
+[[tool.mypy.overrides]]
+module = ["minio", "minio.*"]
+ignore_missing_imports = true
+
 # PyYAML ships no inline types and types-PyYAML is not a dev dependency.
 [[tool.mypy.overrides]]
 module = "yaml"