fix(plugins): stamp surface identity at record time, not send time

Six defects in 0.3.x plugin telemetry. Defects 1, 2 and 6 were not three bugs:
they were one spool protocol getting three properties wrong.

Identity was decided by the wrong process. `harness` was stamped in record(),
correctly, but `source` was read from a module global in flush() — so whichever
process drained the spool named every event in it. Two processes never call
init(): mcp_server.py, and the detached `python3 telemetry.py` sender that
spawn_flush() starts. record() now stamps source beside harness, and the build
generates core/_harness_id.py per host so identity resolves with no init() call
at all. That also unifies two defaults that disagreed (`<host>_plugin` vs
`MEM0_<HOST>_PLUGIN`), which could yield three source values for one plugin.

Ownership was inferred, not held. Path.replace is os.rename, which preserves
mtime, so a claim made after a quiet minute inherited the spool's age and was
stealable the instant it existed. Claims are touched on creation and the
per-batch rewrite doubles as a lease heartbeat.

Progress was not durable. flush() returned on the first failed batch without
truncating, so the retry re-posted from index 0 — 150 events delivered 250
times. It now rewrites the claim with the unsent remainder after every batch,
bounding a crash to one repeated batch, and each event carries a uuid.

Parked batches starved. They were only reachable when no spool existed, and
because sessions keep recording there usually was one, so a batch parked by a
failed send waited until the 7-day expiry deleted it unsent — despite its own
presence being what starts the sender. flush() drains them in the same run, and
expiry now applies only after a genuine retry has failed.

code.install counted upgrades and repeat sessions. is_first_run() read the
identity file, which only a successful flush writes, so an offline user recorded
an install every session forever. A dedicated install-state.json is claimed
atomically at record time; a non-empty data directory reads as an upgrade.

The docs called this anonymous. Every event carries the account email, and the
hashes were unsalted SHA-256 over a git remote URL or an absolute path
containing the username. READMEs, the module docstring and a new docs section
now say what the code does, and repo/session digests are salted per install.

A cached email outlived an API key change. It is now re-resolved when the key's
fingerprint differs, and $identify aliases anonymous->email only — aliasing one
account to another merges person profiles irreversibly.

All six shipped green because the shared core's only tests lived under one host,
behind a conftest that calls init() at import. Core behaviour was never
exercised uninitialised. Adds agent-plugin-core/tests with no init, including
subprocess tests and coverage for the portable plugin, which has no flush worker
and would pass a native-only test vacuously.

Also puts the three surface headers on the SDKs, CLIs and integrations, and
corrects a README claiming ZAPIER/STRANDS were already in the platform allowlist.

Verified: 59 core tests, 203 claude-code, 11 cursor, 5 codex, 2 kimi, 6
antigravity. ruff and compileall clean. --check clean for all six hosts.
TypeScript changes are not typechecked locally (deps not installed).

Claude-Session: https://claude.ai/code/session_01C7tEmH86HAr7GoAAKCEHZb

integrations/deepseek-plugin/README.md

@@ -86,9 +86,9 @@ Per-call `userId` overrides are rejected unless the operator enables `allowUserO
 
 ## Telemetry
 
-Writes are tagged `source="DEEPSEEK_HARNESS"` so Mem0's backend can attribute usage to this integration. For it to surface by name (rather than bucketing into `OTHERS`), `DEEPSEEK_HARNESS` must be present in the backend's `KNOWN_EVENT_SOURCES` allowlist, a one-line platform change matching the existing `ZAPIER` / `STRANDS` sources.
+Writes are tagged `source="DEEPSEEK_HARNESS"`, which the Mem0 backend recognizes so usage surfaces by name rather than bucketing into `OTHERS`.
 
-The plugin also sends anonymous usage events (which tool ran, duration, result counts, coarse failure kind) so Mem0 can tell how the plugin is used and where it breaks. Queries, memory text, and entity ids are never sent. Turn it off with `MEM0_TELEMETRY=false`.
+The plugin also sends usage events (which tool ran, duration, result counts, coarse failure kind) so Mem0 can tell how the plugin is used and where it breaks. These are **not anonymous**: when an API key is configured they are sent under your Mem0 account email, the same way the SDK attributes its own. Queries, memory text, and entity ids are never sent. Turn it off with `MEM0_TELEMETRY=false`.
 
 ## Status
 

integrations/deepseek-plugin/src/index.ts

@@ -26,10 +26,8 @@ export const name = "mem0";
 export const inject = ["tools", "systemPrompt"];
 
 // Tags writes so Mem0's backend attributes them to this integration in
-// telemetry. The backend keeps recognized values via its KNOWN_EVENT_SOURCES
-// allowlist; unknown values bucket into "OTHERS", so "DEEPSEEK_HARNESS" must be
-// added to that allowlist for usage to surface by name (a one-line backend PR,
-// same pattern as the ZAPIER / STRANDS sources).
+// telemetry. The backend's KNOWN_EVENT_SOURCES allowlist recognizes this value;
+// anything outside it buckets into "OTHERS".
 const SOURCE = "DEEPSEEK_HARNESS";
 
 const DEFAULT_SEARCH_LIMIT = 10;