fix(prometheus): add write permission and clarify plan output location

[craftaholic]

Summary

Fixed #1105
When I tried to use with other un-recommended model (Minimax m2.1) it has some edge cases:

• Prometheus can't write plan file due to missing write tool in its allowed tool to use
• Prometheus actually tried to write tool in $HOME/.claude/.sysiphus/* instead of the current directory

This PR is to solve the issue, make it less ambiguous for promethus by:

• This give the missing permission to write the plan.md file. We already have post hook to check for the prometheus write file in case it tried to write to other location -> this is safe to add.
• Make the prompt more clear so prometheus always knows to create the plan file in the working dir of the current session.

Changes

• Add write: allow to PROMETHEUS_PERMISSION to enable plan file creation
• Clarify plan output location to use current workspace .sisyphus/ directory
• Add explicit guidance to avoid ~/.sisyphus/ and absolute paths

Screenshots

Testing

bun run typecheck
bun run build
bun test src/agents

All 38 tests passed

Related Issues

Related to #1105

[cubic-dev-ai]

No issues found across 1 file

Confidence score: 5/5

• Automated review surfaced no issues in the provided summaries.
• No files require special attention.

[tinhtq]

LGTM

[dchai94]

LGTM +1