Always show the guide sources strip

[shaug]

TL;DR

Keep the guide source-count strip visible in both default and personalized states, and remove the redundant hero statistics line.

Summary

• render the sticky source strip by default with templated “Counting all N sources.” wording
• retain the existing personalized “Counting N of M sources.” state and Edit sources action without layout jumps
• reduce the hero to kicker, title, and tagline while preserving detailed-PDF pagination safety
• update the design ledger, browser behavior coverage, migration expectations, and approved visual baselines

Validation

• make check
• fresh full-diff review: clean, no findings

Fixes #177