fix(#130): default idempotency key to install-time stamp, not release revision

[saadqbal]

Closes #130.

Summary

• ingestor/templates/_helpers.tpl: when .Values.idempotencyKey is unset, derive the key from <release>-<unix-epoch> instead of <release>-<revision>. Helm resets revisions to 1 after helm uninstall, so the old default collided on the very common "uninstall → fix something → reinstall" loop and tripped jobs-manager's 409 guard.
• ingestor/values.yaml: doc-comment flipped to describe the new default and call out why a revision-derived default is the wrong shape here. Override path is reframed as opt-in for at-most-once semantics.
• ingestor/README.md: frequently-overridden table row updated to match.
• ingestor/Chart.yaml: bumped 0.1.0 → 0.1.1.

The opt-in path (--set idempotencyKey=...) is unchanged — the value is still passed through verbatim, so callers who want stable replays still get them.

Why %s-%s, not %s-%d

Sprig's unixEpoch returns a string, not an int. The first cut of this patch used %d and rendered my-dataset-%!d(string=1779196370) — caught by the local helm template smoke test before commit.

Test plan

Template-level (run locally, passes):

• helm lint ./ingestor --set-file ingestConfig=... → clean.
• Two consecutive helm template invocations (default path) produce different idempotency_key values. Verified: my-dataset-1779196406 then my-dataset-1779196408 two seconds later.
• Render with a different release name picks up the new name: other-name-1779196408.
• Override path is verbatim: --set idempotencyKey=stable-uuid-abc → "idempotency_key":"stable-uuid-abc".

Cluster-level (owner of jobs-manager runtime needs to validate against a live cluster — I can't reach one from this branch):

• helm install my-dataset ./ingestor --set-file ingestConfig=./test.yaml → uninstall → reinstall with the same release name + same ingest.yaml → second install creates a fresh ingestor Job (different ingest-job-<hash>), not a 409.
• helm install my-dataset ./ingestor --set-file ingestConfig=./test.yaml --set idempotencyKey=foo → uninstall → reinstall with the same key + same config → jobs-manager returns 200 replay, no second Job created.

Refs

• Sibling to #125 / #126 and #127 / #128, which together with this PR finish polishing the customer-facing ingestor install loop.
• The 409 itself is enforced by jobs-manager in client-runtime — that behavior is correct and unchanged; this PR only changes what the chart hands to it.

🤖 Generated with Claude Code

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Note

Low Risk
Low risk Helm-template change that only affects the default idempotencyKey generation; primary risk is behavior change for users who relied on revision-based dedupe semantics implicitly.

Overview
Updates the ingestor Helm chart so the default idempotencyKey is derived from <release>-<unix-epoch> (via now | unixEpoch) instead of <release>-<revision>, preventing collisions when a release is uninstalled and reinstalled under the same name.

Documentation is aligned to the new default and the override semantics (stable UUID for at-most-once replay), and the chart version is bumped to 0.1.1.

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[LukasWodka]

👋 Heads-up — Code review queue is at 20 / 8

Above the WIP limit. The team convention is to review existing PRs before opening new work.

Open PRs currently in Code review (oldest first):

• client#131 — feat(Move ingestor ServiceAccount into parent client chart (shared resource) #129): parent client chart owns the shared ingestor ServiceAccount (1.3.4) · author: @saadqbal · no reviewer assigned
• client-runtime#36 — Bump requests from 2.32.3 to 2.33.0 in /Node-deploy · author: @dependabot · no reviewer assigned
• client-runtime#37 — Bump black from 25.1.0 to 26.3.1 in /Node-deploy · author: @dependabot · no reviewer assigned
• client-runtime#38 — Bump requests from 2.32.3 to 2.33.0 · author: @dependabot · no reviewer assigned
• client-runtime#39 — Bump black from 25.1.0 to 26.3.1 · author: @dependabot · no reviewer assigned
• data-ingestors#96 — Add release-time smoke test for ingestor image · author: @saadqbal · no reviewer assigned
• design-system#19 — fix: un-track coverage/ and node_modules/ from git · author: @LukasWodka · no reviewer assigned
• docs#3 — Block bots from crawling Mintlify static assets · author: @LukasWodka · reviewer: @saadqbal
• model-zoo#74 — Add 9 MLM model variants and remove warmstart · author: @shujaatTracebloc · reviewer: @divyasinghds
• tracebloc-client#296 — chore(deps): bump ray from 2.44.1 to 2.55.0 in /use_cases · author: @dependabot · no reviewer assigned

Pull from review before opening new work. (This is a nudge from the kanban WIP check, not a block.)