[BUG]: The capella research timeout is too short

Describe the bug

The capella research run timeout and it seems it needed more time higher than 3h hardcoded.

There is two way to fix this problem: 1- Add env to set it dynamically instead of hardcoding it. 2- Change the 3h to 4-5 hours.

https://github.com/KeygraphHQ/shannon/blob/25b90b0611f15ab945e051dfee8ae78600d3a002/apps/worker/src/ai/sast/capella/temporal/activity-types.ts#L282

Steps to reproduce

1. Run shannon
2. Wait until the ten step capella research start

Expected behaviour

Because this sast version is too time consuming, we expect the timeout is more than 3h.

Actual behaviour

3h timeout seems not enough and it is harcoded and cannot set by env variable.

Pre-submission checklist (required)

• I have searched the existing open issues and confirmed this bug has not already been reported.
• I am running the latest released version of shannon.

If applicable

• I have included relevant error messages, stack traces, or failure details.
• I have checked the workspaces folder for logs and pasted the relevant errors.
• I have inspected the failed Temporal workflow run and included the failure reason.
• I have included clear steps to reproduce the issue.
• I have redacted any sensitive information (tokens, URLs, repo names).

Debugging details

No response

Screenshots

No response

CLI mode

npx (@keygraph/shannon)

Provider

Anthropic (API key)

Full command with all flags used (with redactions)

npx @keygraph/shannon start -u https://example.com -r . -c ../shannon-staging.full.yaml

OS (with version)

Linux24.04

Node.js version ('node -v')

v24.12.0

Docker version ('docker -v')

29.6.1

Additional context

No response