Drop the OsmAnd-recolor map theme, add offline labels and a lighter palette nudge

Remove osmand-style.js (the per-layer color-patching approach) and its
docs entirely — back to the plain OpenFreeMap "liberty" style online,
and protomaps-themes-base's stock theme offline as the base.

Offline maps previously had no text labels at all: the
protomaps-themes-base layers() call never passed a lang option, which
is required to include its label layers. Fixed, backed by vendored
Noto Sans Regular/Italic/Medium glyph PBFs (ranges 0-255 and 256-511
only — Basic Latin + Latin-1 Supplement + Latin Extended-A, enough for
accented Central European place names; other scripts won't render
offline). Verified against the actual offline.pmtiles vector layer
schema that the name/name:en/script fields this expects are present.

Also nudge a handful of OFFLINE_THEME color roles (background, water,
wood, buildings, the two road-importance tiers) towards the online
style's actual palette (sampled from its style JSON) so switching
Online/Offline doesn't look like two different apps — deliberately
partial, not the removed full recolor.

docs/third-party-notices.adoc

@@ -23,6 +23,20 @@ BSD-3-Clause licensed.
 | https://github.com/protomaps/basemaps
 |===
 
+Offline map text labels need font glyphs too (see
+`docs/architecture.adoc`), vendored under `public/vendor/fonts/` —
+SIL Open Font License, not BSD-3-Clause like the above:
+
+[cols="1,2"]
+|===
+| Asset | Source
+
+| Noto Sans Regular/Italic/Medium glyph PBFs (ranges `0-255`,
+`256-511` only)
+| https://github.com/protomaps/basemaps-assets[protomaps/basemaps-assets]
+(`fonts/`, `OFL.txt` included alongside)
+|===
+
 The online map style (not vendored, fetched at runtime when the
 "Online" layer is selected) is
 https://tiles.openfreemap.org/styles/liberty[OpenFreeMap "liberty"],