Enable CI checks for PRs targeting feature-lib branch

[Copilot]

PRs targeting feature-lib were not triggering the same CI checks (build and lint) as PRs targeting main.

Changes

• .github/workflows/build.yml: Added feature-lib to pull_request trigger branches
• .github/workflows/lint.yml: Added feature-lib to pull_request trigger branches

# Before
pull_request:
  branches: [ "main" ]

# After  
pull_request:
  branches: [ "main", "feature-lib" ]

PRs targeting feature-lib now run the full build and lint check suite.

Original prompt

Please update this repo so that all of the checks that we run when we target the main branch in a PR gets triggered when target the feature-lib branch please update this in the feature-lib branhc, dont update amin

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