* fix(quality): preserve cursor iteration and option validation
Keep prefetched rows on ManagedCursor so partial loops and explicit fetches share one position, and stop existing iterators after close or retirement. Preserve chunked reads and native SQLite result lifetime on reexecution and errors.
Catch OptionError before ValueError so legacy auto-tag requests receive the actual validation error. Remove the overwritten ViewerJS title option.
Regression tests failed before the fixes for lost rows, reads after close/retirement, and misleading option errors. Focused Python checks pass; cursor checks also pass on Python 3.13 and 3.14. Refs #321.
* fix(quality): make the test doubles legal raises and hashes
The fake queue no longer raises an attribute that starts as None. The
oversized kind records hashes instead of raising from __hash__, which
also catches a hash that production code swallows. Hostile.__bool__
raises the TypeError a truth test may raise.
* fix(quality): drop the extra saveCoverage argument
* refactor(quality): remove assignments that are overwritten before use
* refactor(quality): remove the remaining overwritten test assignments
* refactor(quality): drop imports repeated inside functions
* refactor(quality): give duplicate identity keys one shape
* refactor(quality): name the unused job event loop variable
* refactor(quality): release model gates in finally, not except BaseException
* refactor(quality): end the job runners with an explicit return
* refactor(quality): use the precise unittest asserts
* refactor(quality): import unittest.mock one way in the tests
* fix(quality): say why each empty except is safe, log the broad ones
* refactor(quality): stop binding values the tests never read
* refactor(quality): remove the unused preview aliases and tag page query
* refactor(quality): remove re-exports nothing imports
* refactor(quality): parenthesize deliberate string joins in lists
* refactor(quality): remove unused JavaScript variables and imports
* refactor(quality): use the precise assert in the model status test
Each tests/browser/server.py grew from about 13 MB to 0.6-1 GB RSS over
a page-workflow shard while its Python heap stayed near 12 MB. glibc
raises its mmap threshold (up to 32 MiB) after a large free, so the
seeder's image-sized buffers came from per-thread malloc arenas, which
fragmented and kept their pages. The server now fixes the threshold at
glibc's 128 KiB start value (mallopt M_MMAP_THRESHOLD) before it starts,
so large blocks go back to the OS on free. No memory limit is set; off
glibc it does nothing.
Closes#516
Vito