mcp: add readonly guard to config add/remove handlers

[Elvand-Lie]

The deploy and delete handlers check s.readonly and refuse to act in readonly mode. However, the six config mutation handlers (configEnvsAdd, configEnvsRemove, configLabelsAdd, configLabelsRemove, configVolumesAdd, configVolumesRemove) execute unconditionally, allowing an AI agent to modify func.yaml even when readonly mode is active.

Add the same readonly guard to all six config mutation handlers, consistent with deploy and delete.

Changes

• Add s.readonly guard to configEnvsAddHandler and configEnvsRemoveHandler
• Add s.readonly guard to configLabelsAddHandler and configLabelsRemoveHandler
• Add s.readonly guard to configVolumesAddHandler and configVolumesRemoveHandler

Fixes #3704

Release Note

NONE

Docs

NONE

[knative-prow]

Hi @Elvand-Lie. Thanks for your PR.

I'm waiting for a knative member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work.

Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

Details

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[codecov]

Codecov Report

❌ Patch coverage is 96.29630% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 54.05%. Comparing base (d7b93f6) to head (8bee273).

Files with missing lines	Patch %	Lines
pkg/mcp/tools_build.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3708      +/-   ##
==========================================
+ Coverage   54.00%   54.05%   +0.04%     
==========================================
  Files         200      200              
  Lines       23687    23711      +24     
==========================================
+ Hits        12792    12816      +24     
  Misses       9660     9660              
  Partials     1235     1235              

Flag	Coverage Δ
e2e	34.02% <0.00%> (-0.04%)	⬇️
e2e go	29.36% <0.00%> (-0.04%)	⬇️
e2e node	25.69% <0.00%> (-0.03%)	⬇️
e2e python	29.69% <0.00%> (-0.04%)	⬇️
e2e quarkus	25.82% <0.00%> (-0.01%)	⬇️
e2e rust	25.29% <0.00%> (-0.03%)	⬇️
e2e springboot	23.98% <0.00%> (-0.03%)	⬇️
e2e typescript	25.81% <0.00%> (-0.03%)	⬇️
e2e-config-ci	26.86% <0.00%> (-0.05%)	⬇️
integration	15.67% <0.00%> (-0.01%)	⬇️
unit macos-14	43.11% <95.23%> (+0.05%)	⬆️
unit macos-latest	43.11% <95.23%> (+0.05%)	⬆️
unit ubuntu-24.04-arm	43.42% <96.29%> (+0.05%)	⬆️
unit ubuntu-latest	43.96% <95.23%> (+0.05%)	⬆️
unit windows-latest	43.18% <95.23%> (+0.06%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[gauron99]

/ok-to-test
/lgtm
/approve

[knative-prow]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Elvand-Lie, gauron99

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Details

Needs approval from an approver in each of these files:

• OWNERS [gauron99]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[gauron99]

/hold for @lkingland input

[gauron99]

/retest

[lkingland]

/unhold

Patch matches the existing deploy/delete inline-check convention, addresses a real readonly bypass, and shouldn't wait on hypothetical refactors. If #3771 reshapes this code later, the readonly logic will move with it. Let's land.

Please rebase and we can land it.

[knative-prow]

New changes are detected. LGTM label has been removed.

[Elvand-Lie]

@gauron99 Just noticed this PR recently and I think I've rebased it if you have the time please take a look. Thanks.