feat: Add custom path suffix support for Custom Providers

[Yu-Xiao-Sheng]

This change allows Custom Providers to specify a custom path suffix instead of hardcoding /v1/chat/completions, which was causing issues with providers like GLM Coding Plan that use different URL structures.

Changes:

• Added path_suffix column to CustomProvider entity (nullable, defaults to null)
• Modified buildCustomEndpoint to accept optional pathSuffix parameter
• Updated default path from /v1/chat/completions to /chat/completions
• Updated proxy.service.ts to pass path_suffix when building custom endpoint

This enables GLM Coding Plan and other providers with non-standard URL structures to work correctly without requiring hardcoded provider configurations.

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Summary by cubic

Adds custom path suffix support for Custom Providers and per‑agent request timeouts. Keeps the default /v1/chat/completions and uses agent-specific timeouts when forwarding to providers.

• New Features
  • Custom Providers: add nullable path_suffix to entity/DTOs/controller responses and proxy; buildCustomEndpoint accepts pathSuffix and normalizes a leading slash; defaults to /v1/chat/completions when null for backwards compatibility.
  • Frontend: add path_suffix input to the Custom Provider form; update CustomProviderData, createCustomProvider, and updateCustomProvider to handle it.
  • Agent timeouts: add request_timeout_ms to Agent (with migration); extend rename endpoint/DTO to accept it; include in analytics responses; ProxyService reads the agent timeout and passes it to ProviderClient.forward, which now supports a custom timeout; default remains 180s.
  • Settings UI: add “Request timeout (seconds)” field; renameAgent API sends request_timeout_ms; empty uses the default; input validated (min 10s, max 3600s).

^{Written for commit 1ba0af4. Summary will update on new commits.}

[cubic-dev-ai]

1 issue found across 3 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="packages/backend/src/routing/proxy/provider-endpoints.ts">

<violation number="1" location="packages/backend/src/routing/proxy/provider-endpoints.ts:144">
P1: The new default custom-provider path (`/chat/completions`) breaks existing providers that relied on the previous `/v1/chat/completions` behavior when `path_suffix` is null.</violation>
</file>

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[Yu-Xiao-Sheng]

1 issue found across 3 files
Prompt for AI agents (unresolved issues)

Since this is your first cubic review, here's how it works:

* **cubic automatically reviews your code** and comments on bugs and improvements

* **Teach cubic by replying to its comments**. cubic learns from your replies and gets better over time

* **Add one-off context when rerunning** by tagging `@cubic-dev-ai` with guidance or docs links (including `llms.txt`)

* **Ask questions** if you need clarification on any suggestion

Reply with feedback, questions, or to request a fix. Tag @cubic-dev-ai to re-run a review.

Thanks @cubic-dev-ai for the review! I've fixed the P1 backwards compatibility
issue.

Fix: Restored the default path to /v1/chat/completions (using
openaiPath) when path_suffix is null. This ensures existing custom
providers continue to work as before.

For GLM Coding Plan users: They should explicitly set path_suffix = '/chat/completions' to use the correct endpoint (without /v1).

The updated code now:

• Uses openaiPath (which is /v1/chat/completions) when path_suffix is
  null - preserving backwards compatibility
• Allows providers like GLM Coding Plan to override by setting path_suffix = '/chat/completions'

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 96.01%. Comparing base (fa074ca) to head (1ba0af4).
⚠️ Report is 57 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1195      +/-   ##
==========================================
- Coverage   98.54%   96.01%   -2.53%     
==========================================
  Files          93       13      -80     
  Lines        7359      678    -6681     
  Branches     2819      192    -2627     
==========================================
- Hits         7252      651    -6601     
+ Misses         80        0      -80     
  Partials       27       27              

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[brunobuddy]

@Yu-Xiao-Sheng that is a massive PR that is not fixing any issue on GitHub. Please create the issue you are solving first and then attach the PR to it