fix(performance): use simple height estimation instead of PIL rendering

- Replace estimate_block_height (PIL-based) with estimate_simple_height (word wrap)
- Update viewport filter tests to match new height-based filtering (~4 items vs 24)
- Fix CI task duplication in mise.toml (remove redundant depends)

Closes #38
Closes #36

mise.toml

@@ -10,7 +10,8 @@ uv = "latest"
 # =====================
 
 test = "uv run pytest"
-test-cov = { run = "uv run pytest --cov=engine --cov-report=term-missing", depends = ["sync-all"] }
+test-cov = { run = "uv run pytest --cov=engine --cov-report=term-missing -m \"not benchmark\"", depends = ["sync-all"] }
+benchmark = { run = "uv run python -m engine.benchmark", depends = ["sync-all"] }
 lint = "uv run ruff check engine/ mainline.py"
 format = "uv run ruff format engine/ mainline.py"
 
@@ -50,7 +51,7 @@ clobber = "git clean -fdx && rm -rf .venv htmlcov .coverage tests/.pytest_cache
 # CI
 # =====================
 
-ci = { run = "mise run topics-init && mise run lint && mise run test-cov", depends = ["topics-init", "lint", "test-cov"] }
+ci = "mise run topics-init && mise run lint && mise run test-cov && mise run benchmark"
 topics-init = "curl -s -d 'init' https://ntfy.sh/klubhaus_terminal_mainline_cc_cmd > /dev/null && curl -s -d 'init' https://ntfy.sh/klubhaus_terminal_mainline_cc_resp > /dev/null && curl -s -d 'init' https://ntfy.sh/klubhaus_terminal_mainline > /dev/null"
 
 # =====================