docs: expand documentation and bump version to 0.5.0

- New pages: Installation, Remote Sources, Guides, Troubleshooting
- Examples page restructured as a visual gallery with new screenshots
  (diff, highlight, log-scale before/after, archive, interactive SVG)
- Images moved to docs/images/; make_examples_images.sh added
- Use cases section added to README and home page
- API snippets tested; t_scan param made optional with default 0.0
- Home directory replaced with ~ in Scanning… messages
- make_docs_images.sh --size flag corrected to --canvas
- pre-commit: mypy hook uses --all-extras; docs/images/ excluded from large-file check

chore: bump version to 0.4.5, add changelog entries

build: add serve-docs Makefile target

fix(cli): CLIG compliance — secrets, flags, output routing

- Remove --github-token, --ssh-password, --password flags; use env vars
  (GITHUB_TOKEN) or --*-file alternatives instead
- Remove non-standard SSH_KEY / SSH_PASSWORD env var reads
- Drop single-letter shortcuts for infrequent options (-c, -r, -n, -w,
  -s, -b/-B, -N) to avoid conflicts with CLI conventions
- Rename --logscale → --log-scale (hyphen convention)
- Route all status/info messages to stderr consistently
- Honour $COLUMNS/$LINES for terminal size when ioctl unavailable
- Show help when `dirplot map` is run with no args in a TTY
- Update all docs and CHANGELOG for 0.4.3

feat: add overview subcommand at help position #2

fix(windows): fix remaining str(repo/fp) → .as_posix() in R and C cases

The previous fix missed the renamed (R) and copied (C) diff status branches
which used old_fp/new_fp variable names instead of fp.

fix(build): exclude large local artifacts from sdist

movies/, output/, and other local files (*.cast, *.jsonl, *.png, *.mp4)
were not in .gitignore so hatchling bundled them into the sdist, causing
uv build to hang on multi-gigabyte files.

chore: bump version to 0.3.3

docs: regenerate example images with improved label rendering

fix: minor issue in changelog