feat(scan): split scan spinner into report-creation and page-compiling stages

[v3nant]

Summary

• Splits the single "Scanning for EOL packages" spinner into two stages: report creation (ora spinner) and page compiling (cli-progress bar).
• On report creation success, the spinner now shows "Created Scan Report {reportId}"; on failure, "Failed to Create Scan Report".
• Page fetching now shows a "Compiling Report Results" progress bar tracking completed/total pages, updated as each page resolves.
• Fixes a latent concurrency bug: page query promises were constructed (and thus started) eagerly for the whole report at once, so concurrentPageRequests never actually bounded in-flight requests. Queries are now built per-batch and progress is reported per-page as each settles.

Test plan

• npm run typecheck
• npx vitest run (247 passing)
• biome check on changed files
• Manual: run hd scan eol against an SBOM and confirm the two-stage spinner/progress bar behavior