fix(installer): attribute rejected-zone hint to its real source (Bugbot #356)

[saadqbal]

What

Fixes the one Cursor Bugbot finding on #356 ("Misleading invalid-zone failure hint", scripts/lib/provision.sh#L85-88).

When client create rejects a location as not a valid carbon zone, _report_create_failure always said the zone was auto-derived from the timezone and pointed the operator at TRACEBLOC_CLIENT_LOCATION as the remedy. But when the rejected value came fromTRACEBLOC_CLIENT_LOCATION, that hint reads as "your override was ignored" — misleading.

How

• Track the location's origin in provision_client: "env" when pinned via TRACEBLOC_CLIENT_LOCATION, "auto" when timezone-derived.
• Pass it as a third arg to _report_create_failure, which now words the fix hint to the actual source (defaults to "auto" if omitted — back-compatible).
• Adds 3 unit tests to provision.bats (env source, auto source, default).

All 26 provision.bats tests pass locally. bash -n clean.

Merging into develop updates the develop→main release PR #356.

Rolls up under the location-drop task (#356) — Bugbot drive-by, no separate ticket.

---

Note

Low Risk
Installer-only messaging and test coverage; no change to provisioning logic, credentials, or API behavior.

Overview
When client create rejects a carbon zone, _report_create_failure no longer always blames timezone auto-derivation. provision_client records whether the location came from TRACEBLOC_CLIENT_LOCATION (env) or timezone detection (auto), passes that into _report_create_failure, and the invalid-zone hints point operators at the right fix (correct the env var vs set TRACEBLOC_CLIENT_LOCATION). The third argument defaults to auto for backward compatibility.

Three provision.bats cases cover env-sourced, auto-sourced, and omitted-source behavior. scripts/manifest.sha256 is updated for provision.sh.

^{Reviewed by Cursor Bugbot for commit 9f7168d. Bugbot is set up for automated code reviews on this repo. Configure here.}

[LukasWodka]

👋 Heads-up — Code review queue is at 37 / 30

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

Open PRs currently in Code review (oldest first):

• averaging-service#183 — docs: SafeTensors deployment-order & resume-safety runbook (epic ci: drop push-tags trigger from release-helm-chart.yaml to fix race with release-published #116) · author: @shujaatTracebloc · reviewer: @saadqbal
• averaging-service#184 — test(weights): shared SafeTensors golden-corpus drift guard + declare safetensors dep (SEC-03) · author: @LukasWodka · no reviewer assigned
• averaging-service#185 — test(weights): average a real SafeTensors edge + a legacy edge in one cycle — SEC-03 §8 · author: @LukasWodka · no reviewer assigned
• backend#1093 — chore(deps): bump django from 5.2.14 to 5.2.15 · author: @dependabot · no reviewer assigned
• backend#1119 — perf(api): cache ChoiceGroup + score-formula reference endpoints (#981 item 4, part 1) · author: @aptracebloc · no reviewer assigned
• backend#1122 — perf(api): cache the anonymous competition-template list (#981 item 4, part 2) · author: @aptracebloc · reviewer: @saqlainsyed007
• cli#340 — chore: back-merge main → develop (adopt cobra 1.10.2 + reconcile drift) · author: @saadqbal · no reviewer assigned
• client#356 — main -> Stop prompting for location during registration, auto-derive from timezone · author: @saadqbal · no reviewer assigned
• data-ingestors#361 — feat(ingest): emit per-column feature_stats for combine-time normalization (main -> Release v1.9.5: location-drop + installer hardening #360) · author: @divyasinghds · no reviewer assigned
• data-ingestors#372 — fix(validators): use redaction.column_preview for mask_id error column lists · author: @divyasinghds · no reviewer assigned

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