fix(android): type literal %s correctly in the adb input text fallback

[theworker02]

Fixes #160

Problem

Android's input text turns every %s into a space and has no escape for a literal %s. _escape_for_adb_text() encodes spaces as %s but leaves real %s sequences alone, so text such as Hello %s or 50%sale was typed as Hello / 50 ale whenever the native fallback ran. AndroidInputIME.type_text() hits this for all ASCII text, because its fast path always uses input text.

Change

• Added _adb_input_text_commands(line) in adb_driver.py. It splits the line at each literal %s so that % ends one input text command and s starts the next. Each command is decoded on its own, so the trailing % is typed literally. Lines without %s still produce exactly one command, same as before.
• AndroidAdbDriver.input_text() Tier 3 and both input text paths in AndroidInputIME.type_text() use the new helper.
• Removed the duplicate _escape_for_adb_text() from input_ime.py, which now imports the shared helper.

Testing

New tests/unit/test_adb_input_text.py:

• A small decoder that mirrors how input text decodes its argument (shell backslash escapes, %s → space), used to assert round-trips for Hello %s, 50%sale, a%s%sb, 100% sure, %%s literal, ends with %, and plain text.
• Exact command output for the plain and split cases.
• End-to-end checks through AndroidAdbDriver.input_text() (native fallback) and AndroidInputIME.type_text() (ASCII fast path).

uv run pytest tests/unit/test_adb_input_text.py tests/unit/test_drivers.py passes, and ruff format --check, ruff check, and pyright --project pyright-core.json are clean.

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