[asulwer]

Closes #13

Shows the place a pattern covers or a number comes from:

• Patterns tab: under each pattern. For example, 602* shows Arizona, 876* Jamaica, +44* United Kingdom and +4420* London, United Kingdom. Nothing is shown when the pattern has too few digits to tell, such as 60* or *.
• Calls tab: in each row's details, e.g. Oct 21, 10:47 AM · Arizona · matches 602*.
• Test a number: e.g. (416) 555-0100 (Ontario, Canada) would ring: no pattern matches it.

How it works:

• Uses libphonenumber-csharp 9.0.41, Google's offline geocoding data. No internet is needed; the app still requests no internet permission.
• It runs only on screen. BlockerService never calls it, so screening speed is unchanged: 0–19 ms on the emulator.
• The data is loaded in the background when the UI starts (PlaceNames.WarmUp), so the first screen doesn't wait.
• For an area-code pattern, the code is filled out with the fake 555-0100 exchange. That way an area code resolves to its state or country, not to whichever town owns a real exchange.

Docs: README, docs/using.md, docs/patterns.md, and a Privacy note in docs/how-it-works.md.

Stacked on #16. This PR's base is edit-pattern-note, so the diff shows only this change. When #16 is merged and its branch deleted, GitHub retargets this PR to master.

Testing

• 25 new unit tests in PlaceNamesTests; all 181 tests pass.
• Release build (trimmed, x64) on the emulator:
  • Patterns tab shows Nigeria, London, United Kingdom, Arizona and Jamaica.
  • A simulated call from (602) 555-9999 was BLOCKED and shown as "Arizona · matches 602*".
  • A call from (416) 555-0100 shows as "Ontario, Canada".
  • Test a number shows the place.

🤖 Generated with Claude Code