fix(tasks): recover resumes from missing branches

[tatoalo]

Problem

A cloud task resume can carry a branch that is unavailable in the task repository. Provisioning currently treats that as a terminal clone failure, so the agent never boots even though its resume history and git checkpoint remain usable.

Why: Resume should remain available when branch metadata is stale or came from secondary repository work. This complements the metadata ownership fix in PostHog/code#4003.

Changes

When Git explicitly reports that a resume branch is missing, retry the clone from the repository default branch. Other clone failures remain terminal. Once booted, the agent can apply its stored git checkpoint as usual

[trunk-io]

😎 Merged manually by @tatoalo - details.

[greptile-apps]

_{Reviews (1): Last reviewed commit: "fix(tasks): recover resumes from missing..." | Re-trigger Greptile}

[github-actions]

🤖 CI report

⚠️ Backend coverage — 12.0% of changed backend lines covered — 14 uncovered

🧪 Backend test coverage

Patch coverage — changed backend lines (products + core): ██░░░░░░░░░░░░░░░░░░ 12.0% (2 / 16)

File	Patch	Uncovered changed lines
products/tasks/backend/temporal/process_task/activities/tests/test_provision_sandbox.py	0.0%	57–58, 70–71, 82, 84, 95
products/tasks/backend/temporal/process_task/activities/provision_sandbox.py	22.2%	692–693, 698, 712–713, 715–716

🤖 Agents: add a test covering the lines above, or note why under "How did you test this code?". Machine-readable gap list: the patch-coverage artifact on this run (gh run download 30621681454 -n patch-coverage), or the coverage-data block at the end of this comment.

Per-product line coverage (touched products)

Product	Coverage	Lines
demo	███████████░░░░░░░░░ 56.3%	1,497 / 2,661
tasks	██████████████░░░░░░ 70.1%	32,778 / 46,780
signals	████████████████░░░░ 81.2%	24,750 / 30,477
cdp	████████████████░░░░ 82.1%	3,285 / 3,999
data_modeling	█████████████████░░░ 85.6%	7,668 / 8,959
notebooks	█████████████████░░░ 86.0%	7,794 / 9,060
actions	█████████████████░░░ 86.6%	717 / 828
cohorts	██████████████████░░ 87.8%	6,181 / 7,040
product_tours	██████████████████░░ 87.9%	1,303 / 1,482
exports	██████████████████░░ 88.2%	7,046 / 7,986
data_warehouse	██████████████████░░ 88.4%	12,192 / 13,798
engineering_analytics	██████████████████░░ 89.3%	6,529 / 7,309
conversations	██████████████████░░ 89.3%	17,600 / 19,701
dashboards	██████████████████░░ 89.4%	5,983 / 6,693
alerts	██████████████████░░ 90.2%	4,458 / 4,942
streamlit_apps	██████████████████░░ 90.7%	2,630 / 2,901
mcp_analytics	██████████████████░░ 90.9%	3,191 / 3,511
error_tracking	██████████████████░░ 91.0%	10,926 / 12,008
slack_app	██████████████████░░ 91.1%	9,664 / 10,610
marketing_analytics	██████████████████░░ 91.2%	12,092 / 13,265
stamphog	██████████████████░░ 91.3%	4,505 / 4,936
product_analytics	███████████████████░ 92.5%	5,849 / 6,321
early_access_features	███████████████████░ 92.6%	1,287 / 1,390
ai_observability	███████████████████░ 92.8%	15,618 / 16,821
surveys	███████████████████░ 93.1%	5,771 / 6,197
posthog_ai	███████████████████░ 93.2%	1,326 / 1,422
web_analytics	███████████████████░ 93.3%	14,911 / 15,976
approvals	███████████████████░ 93.3%	3,437 / 3,682
reminders	███████████████████░ 93.4%	468 / 501
workflows	███████████████████░ 94.0%	7,219 / 7,679
endpoints	███████████████████░ 94.2%	8,655 / 9,192
review_hog	███████████████████░ 94.6%	8,101 / 8,563
skills	███████████████████░ 94.6%	3,158 / 3,337
experiments	███████████████████░ 95.4%	25,938 / 27,177
logs	███████████████████░ 95.5%	10,440 / 10,937
annotations	███████████████████░ 96.2%	732 / 761
revenue_analytics	███████████████████░ 96.3%	1,887 / 1,960
feature_flags	███████████████████░ 96.4%	17,488 / 18,144
replay_vision	███████████████████░ 96.4%	16,081 / 16,679
user_interviews	███████████████████░ 96.5%	2,638 / 2,734
customer_analytics	███████████████████░ 97.1%	10,444 / 10,758
warehouse_sources	███████████████████░ 97.3%	359,119 / 369,166
data_catalog	████████████████████ 97.7%	2,588 / 2,648
pulse	████████████████████ 98.4%	2,017 / 2,049

Report-only. Patch coverage = changed backend lines covered vs origin/master. Sorted lowest first.
Known gaps: lines covered only by Temporal tests show as uncovered; core line numbers may drift if master changed the same file.

[stamphog]

Contained fix to cloud task sandbox provisioning that retries the clone against the default branch when a resume's saved branch is missing, with a matching regression test; author is on the owning team and no risky-territory surface (auth, billing, data model, API contract, CI/deploy, deps) is touched.

• Author wrote 0% of the modified lines and has 82 merged PRs in these paths (familiarity MODERATE).
• 👍 on the PR from greptile-apps[bot], hex-security-app[bot].

Gate mechanics and policy version

Gate		Result
prerequisites	✓	all clear
deny-list	✓	no deny categories matched
size	✓	27L, 1F substantive, 81L/2F incl. docs/generated/snapshots — within ceiling
tier	✓	T1-agent / T1b-small (81L, 2F, single-area, fix)
stamphog 2.0.0b3		.stamphog/policy.yml @ def52de · reviewed head 9c76e09

[deployment-status-posthog]

Deploy status

Environment	Status	Deployed At	Workflow
dev	✅ Deployed	2026-07-31 12:43 UTC	Run
prod-us	✅ Deployed	2026-07-31 13:07 UTC	Run
prod-eu	✅ Deployed	2026-07-31 13:09 UTC	Run