v0.7.0

Added

• Mirror mode: automatic canvas fit on mismatched-resolution monitors
  (#24). Mirror now sizes the shared tte canvas to the smallest output's
  cell grid by default — no config needed — so mismatched-resolution monitors
  render byte-identical out of the box (previously you had to set
  MIRROR_CANVAS_COLS/ROWS by hand; #14). The launcher can't measure cell
  metrics without a terminal, so each mirror surface records its cell grid to a
  .cell-metrics cache the launcher reads next launch; the first run on a new
  monitor or font layout calibrates and applies the fit from the next launch.
  Matched-resolution setups are unchanged (the fit equals the full-screen
  canvas, so it's skipped), and an explicit MIRROR_CANVAS_COLS/ROWS still
  wins. When the auto-fit box is smaller than the shared logo it's used anyway
  with a warning, since it must fit the smallest output.
• Mirror mode: pixel-identical rendering across mismatched-resolution
  monitors (#14). Two new config keys, MIRROR_CANVAS_COLS and
  MIRROR_CANVAS_ROWS, lock tte's canvas to a fixed cell box in mirror mode
  (--canvas-width/--canvas-height, centered via the --anchor-canvas c
  already passed at every call site). Because the animated region is then the
  same cell grid on every output, tte's deterministic RNG renders
  byte-identical animations even when the monitors differ in resolution —
  previously mirror only matched on equal-resolution outputs and otherwise
  played the same effect with a different layout. Manual override of the
  automatic fit above: both must be positive integers to take effect; a blank,
  garbage, or half-set value defers to the auto-fit. Like MIRROR_INTERVAL,
  it's an advanced config-file knob and is not surfaced in the Noctalia plugin
  UI.

Fixed

• Driver dropped options passed after the command word. main() stopped
  parsing at the first positional, so niri-screensaver run --seed N --logo X
  — exactly how the launcher spawns each surface — silently discarded --seed
  and --logo. Mirror mode therefore never received its shared seed and fell
  back to independent per-monitor RNG on real hardware (it had only been
  mock-tested). Options are now parsed in any position; the command is the first
  positional and an effect name the second. This is what makes mirror's shared
  seed/logo (and the #24 canvas flags) actually reach tte.