mod: Phase 1 - bring forward mod-exclusive files with ActivityManager migration

Brings ~55 mod-exclusive files to the upstream-based mod/master-resync branch:

Activities (migrated to new ActivityManager pattern):
- Clock/Time: SetTimeActivity, SetTimezoneOffsetActivity, NtpSyncActivity
- Dictionary: DictionaryDefinitionActivity, DictionarySuggestionsActivity,
  DictionaryWordSelectActivity, LookedUpWordsActivity
- Bookmark: EpubReaderBookmarkSelectionActivity
- Book management: BookManageMenuActivity, EndOfBookMenuActivity
- OPDS: OpdsServerListActivity, OpdsSettingsActivity
- Utility: DirectoryPickerActivity, NumericStepperActivity

Utilities (unchanged):
- BookManager, BookSettings, BookmarkStore, BootNtpSync
- Dictionary, LookupHistory, TimeSync, OpdsServerStore

Libraries: PlaceholderCover, TableData, ChapterXPathIndexer
Scripts: inject_mod_version, generate_book_icon, preview_placeholder_cover
Docs: KOReader sync XPath mapping

Migration changes:
- ActivityWithSubactivity -> Activity base class
- Callback constructors -> finish()/setResult() pattern
- enterNewActivity() -> startActivityForResult()
- Activity::RenderLock&& -> RenderLock&&

These files won't compile yet - they reference mod settings and I18n
strings that will be added in subsequent phases.

Made-with: Cursor

chat-summaries/2026-02-21_port-pr1055-byte-framebuffer.md

@@ -0,0 +1,27 @@
+# Port PR #1055: Byte-level framebuffer writes
+
+**Date:** 2026-02-21
+**Task:** Port upstream PR #1055 (jpirnay) into the mod, including coderabbit review nitpick.
+
+## Changes made
+
+### `lib/GfxRenderer/GfxRenderer.h`
+- Added two private method declarations: `fillPhysicalHSpanByte` (patterned byte-level span writer) and `fillPhysicalHSpan` (solid-fill wrapper).
+
+### `lib/GfxRenderer/GfxRenderer.cpp`
+- Added `#include <cstring>` for `memset`.
+- Implemented `fillPhysicalHSpanByte`: bounds-clamped byte-level span writer with MSB-first bit packing, partial-byte masking at edges, and `memset` for aligned middle.
+- Implemented `fillPhysicalHSpan`: thin wrapper mapping `state` bool to `0x00`/`0xFF` pattern byte.
+- **`drawLine`**: Replaced per-pixel loops for axis-aligned lines with orientation-aware `fillPhysicalHSpan` calls (vertical lines in Portrait, horizontal lines in Landscape).
+- **`fillRect`**: Replaced per-row `drawLine` loop with orientation-specific byte-level fast paths for all 4 orientations.
+- **`fillRectDither`**: Replaced per-pixel `drawPixelDither` loops for DarkGray/LightGray with orientation-aware `fillPhysicalHSpanByte` using pre-computed byte patterns.
+- **`fillPolygon`** (coderabbit nitpick): Added `fillPhysicalHSpan` fast path for Landscape orientations in the scanline inner loop.
+
+### `mod/prs/MERGED.md`
+- Appended PR #1055 entry with full documentation.
+
+## Differences from upstream
+- `fillPolygon` landscape optimization (from coderabbit review nitpick) was applied as a mod enhancement.
+
+## Follow-up items
+- None. Build verified successful.