fix: support user account all-target runs

[osolmaz]

Opened on behalf of Onur Solmaz (osolmaz).

Summary

github-sane-defaults plan OWNER --all only worked for organizations.
User accounts were routed through the organization repositories endpoint and failed with a 404.
This change makes --all owner-aware, so the same command works for both organizations and user accounts.

What Changed

The CLI now treats targets as owners instead of organizations internally.
It keeps --org as a compatibility alias and adds --owner as the clearer spelling.

• Resolve the target with GET /users/{owner} and branch on the GitHub account type.
• Use /orgs/{org}/repos?type=all for organization owners.
• Use /user/repos?visibility=all&affiliation=owner,collaborator for user owners, then filter by repo.owner.login.
• Add a shared REST pagination helper based on GitHub Link headers.
• Rename app-level target selection from org to owner.
• Update README usage and tests for owner-wide runs.

Testing

I tested the parser, planner, apply path, REST client behavior, docs conventions, and a live plan-only user-account scan.
The live scan verified that osolmaz --all no longer calls the organization-only endpoint.

• npm run check
• npx -y @simpledoc/simpledoc check
• git diff --check
• node dist/src/cli/main.js plan osolmaz --all --token "$(gh auth token)"

Risks

The main behavior change is limited to repository discovery for --all.
Single-repository targets continue to use the same /repos/{owner}/{repo} path.

• User-account scans only include repositories visible to the authenticated token.
• --org remains supported for existing automation.

[osolmaz]

Final report:

• Implemented owner-aware --all repository discovery for organizations and user accounts.
• Kept --org as a compatibility alias and added --owner.
• Added Link-header pagination and REST client coverage for organization and user-account discovery.
• Updated README usage and target-selection tests.

Validation:

• npm run check passed.
• npx -y @simpledoc/simpledoc check passed.
• git diff --check passed.
• node dist/src/cli/main.js plan osolmaz --all --token "$(gh auth token)" passed and planned 152 repositories.
• codex review --base main reported no discrete correctness issues.
• GitHub Actions test passed.