Prepare shinyTZ v0.2.0 for CRAN submission

[Copilot]

Summary

This PR prepares the shinyTZ package for CRAN submission by fixing critical bugs, completing the API, adding CI/CD infrastructure, vignettes, and improving test coverage. A detailed implementation plan and decision log is recorded in inst/docs/cran-prep-plan.md.

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Critical Bug Fixes

Issue	Fix
`%
Three Output functions defined in both datetime-outputs.R AND individual .R files (duplicate exports)	Deleted R/dateOutput.R, R/datetimeOutput.R, R/timeOutput.R
NAMESPACE missing all importFrom statements	Added @importFrom roxygen tags to all R files; NAMESPACE regenerated
zzz.R missing .onLoad() (resource path not auto-registered on package load)	Added .onLoad() to R/zzz.R

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DESCRIPTION / Package Metadata

• Fixed URL and BugReports (now point to Warnes-Innovations/shinyTZ)
• Removed LazyData: true (no data files → was a CRAN NOTE)
• Removed unused DBI and dplyr from Suggests
• Added shinytest2 to Suggests
• Added Config/testthat/edition: 3
• Bumped version to 0.2.0

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API Consistency

• renderDate(): added formatter parameter (was missing vs. renderDatetime())
• renderTime(): added formatter and locale parameters (was missing both)
• All render functions now have consistent (expr, format, formatter, tz, locale, show_tz, env, quoted) signatures
• Added @seealso cross-references on all exported functions

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CI/CD (all new)

Workflow	Description
.github/workflows/R-CMD-check.yaml	Cross-platform R CMD check (Ubuntu/macOS/Windows × R-devel/release/oldrel-1)
.github/workflows/test-coverage.yaml	Test coverage via covr + Codecov upload
.github/workflows/pkgdown.yaml	Build and deploy pkgdown documentation site to gh-pages
.github/copilot-setup-steps.yml	Copilot cloud agent pre-install steps

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Documentation

• README: Added CI/Codecov/License badges; fixed useShinyTZ() missing from Quick Start; corrected license reference (GPL-2, not MIT); updated install URL
• NEWS.md: Added entries for v0.1.1, v0.1.2, v0.2.0 (previously only had v0.1.0)
• Vignettes (new): vignettes/getting-started.Rmd and vignettes/advanced-usage.Rmd
• cran-comments.md: Added CRAN submission checklist and policy notes

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Tests

New/Updated Test File	What It Covers
tests/testthat/test-utils.R	`%
tests/testthat/test-useShinyTZ.R	useShinyTZ() returns correct tag structure with JS src
tests/testthat/test-render-server.R	Render execution with explicit tz override (format strings, timezone conversion, show_tz, custom formatters, invalid timezone fallback)
test-renderDate.R	Added formatter parameter test
test-renderTime.R	Added formatter and locale parameter tests

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Areas for Detailed Review

1. NAMESPACE (manually updated) — Since devtools::document() could not run in the agent environment, the NAMESPACE was updated by hand. Please verify it is complete and correct by running devtools::document() locally and checking for drift.

2. renderTime() signature change — Adding formatter and locale before tz changes the positional argument order. Any existing code using positional args for tz or show_tz would silently break. The NEWS.md entry documents this as a breaking change — please confirm this is acceptable for a pre-1.0 package.

3. .onLoad() resource registration — The zzz.R .onLoad() now calls shiny::addResourcePath() at package load time. This means the resource path is registered even if useShinyTZ() is never called. Please verify this is the desired behavior (no side-effects in non-Shiny contexts).

4. Test coverage — The test-render-server.R tests call render functions directly without a full Shiny session. They work for explicit tz overrides but do not exercise the browser-timezone detection path. Full shiny::testServer() integration tests would require Shiny ≥ 1.7 to be available in the test environment.

5. Vignette examples — All vignette code blocks use r fences but are not evaluated (eval = FALSE is the default for Shiny app examples). Consider whether any examples should be run to generate output for the pkgdown site.