Refactor/components pageshell

[AbuJulaybeeb]

What was done Extracted the repeated main layout wrapper used across pages into a shared, reusable PageShell component to consolidate focus styling, horizontal alignment, page spacing, landmark structure, and keyboard accessibility.

Component Creation: Created src/components/PageShell.tsx rendering

with configurable properties maxWidth (Tailwind max-width suffix, defaulting to "3xl"), gap (spacing scale, defaulting to "6"), and a merged additional className. Fully documented via JSDoc.
Page Migration: Migrated three pages:
src/app/settings/page.tsx (maxWidth="2xl", gap="8")
src/app/docs/page.tsx (maxWidth="3xl", gap="6")
src/app/services/new/page.tsx (maxWidth="xl", gap="6")
Documentation: Documented the PageShell props, options, and rendering rationale in docs/components.md.
Unit Testing: Created src/components/tests/PageShell.test.tsx containing tests for default configuration, custom maxWidth and gap values, fallback logic, custom class name merging, and verification that migrated pages render properly within PageShell.
How it was verified

Verified typescript typecheck:
bash
npm run typecheck

Output: Done with 0 errors

Ran PageShell test suite with 100% statement, branch, function, and line coverage:
bash
npx jest src/components/tests/PageShell.test.tsx --coverage --collectCoverageFrom=src/components/PageShell.tsx --collectCoverageFrom=src/app/docs/page.tsx --collectCoverageFrom=src/app/settings/page.tsx

Output:

----------------|---------|----------|---------|---------|-------------------

File | % Stmts | % Branch | % Funcs | % Lines | Uncovered Line #s

----------------|---------|----------|---------|---------|-------------------

All files | 100 | 100 | 100 | 100 |

app/docs | 100 | 100 | 100 | 100 |

page.tsx | 100 | 100 | 100 | 100 |

app/settings | 100 | 100 | 100 | 100 |

page.tsx | 100 | 100 | 100 | 100 |

components | 100 | 100 | 100 | 100 |

PageShell.tsx | 100 | 100 | 100 | 100 |

----------------|---------|----------|---------|---------|-------------------

Test Suites: 1 passed, 1 total

Tests: 6 passed, 6 total

closes #177

[mikewheeleer]

clean diff — merging now