[AZ-270] [AZ-272] [AZ-279] [AZ-281] [AZ-283] Compose root + FDR schema + 3 Layer-1 helpers

AZ-270: composition root with strategy registry, tier-gated lookup,
topo-order construction, all-or-nothing teardown, StrategyNotLinkedError
payload.
AZ-272: orjson-backed FdrRecord serialise/parse with forward-compat for
unknown payload + top-level fields and canonical overrun-record shape.
AZ-279: pyproj-backed WGS84/ECEF/ENU + OSM slippy-map tile math with
WgsConversionError for shape/range/zoom guards.
AZ-281: strict EngineFilenameSchema build/parse/matches_host with
anchored regex + enum validation; round-trip identity by construction.
AZ-283: dtype-preserving (fp16/fp32) single + batch L2 normaliser with
zero-norm safety and descriptor_metric() source-of-truth.
pyproject.toml pins pyproj>=3.6 and orjson>=3.9 (named-backend deps per
the AZ-272 / AZ-279 contracts). New DTOs LatLonAlt + BoundingBox and
EngineCacheKey + HostCapabilities land in _types/ to back the helper
contracts.
203 unit tests pass (64 new). Review verdict: PASS_WITH_WARNINGS;
findings are perf-NFR deferrals + dep amendment + minor docstring polish.

Co-authored-by: Cursor <cursoragent@cursor.com>

tests/unit/test_az281_engine_filename_schema.py

@@ -0,0 +1,100 @@
+"""AZ-281 — EngineFilenameSchema helper AC tests.
+
+Verifies the contract at ``_docs/02_document/contracts/shared_helpers/engine_filename_schema.md`` v1.0.0.
+"""
+
+from __future__ import annotations
+
+import ast
+import random
+from pathlib import Path
+
+import pytest
+
+from gps_denied_onboard._types.manifests import EngineCacheKey, HostCapabilities
+from gps_denied_onboard.helpers import EngineFilenameSchema, EngineFilenameSchemaError
+
+
+def test_ac1_reference_example_builds_exact_string() -> None:
+    assert (
+        EngineFilenameSchema.build("ultravpr", 87, "6.2", "10.3", "fp16")
+        == "ultravpr__sm87_jp6.2_trt10.3_fp16.engine"
+    )
+
+
+def test_ac2_roundtrip_identity_over_10_random_tuples() -> None:
+    rng = random.Random(2026)
+    for _ in range(10):
+        model = rng.choice(["ultravpr", "netvlad", "megaloc", "selavpr", "salad", "mix_vpr"])
+        sm = rng.choice([72, 86, 87])
+        jp = rng.choice(["5.1", "6.0", "6.2", "6.3"])
+        trt = rng.choice(["8.6", "10.0", "10.3", "10.4"])
+        prec = rng.choice(["fp16", "int8", "mixed"])
+        filename = EngineFilenameSchema.build(model, sm, jp, trt, prec)
+        parsed = EngineFilenameSchema.parse(filename)
+        assert parsed == EngineCacheKey(model, sm, jp, trt, prec)
+
+
+def test_ac3_matches_host_exact_match() -> None:
+    filename = EngineFilenameSchema.build("ultravpr", 87, "6.2", "10.3", "fp16")
+    host = HostCapabilities(sm=87, jetpack="6.2", trt="10.3")
+    assert EngineFilenameSchema.matches_host(filename, host) is True
+
+
+def test_ac4_matches_host_tuple_mismatch_returns_false() -> None:
+    filename = EngineFilenameSchema.build("ultravpr", 87, "6.2", "10.3", "fp16")
+    host_mismatch = HostCapabilities(sm=72, jetpack="6.2", trt="10.3")
+    assert EngineFilenameSchema.matches_host(filename, host_mismatch) is False
+    host_mismatch_trt = HostCapabilities(sm=87, jetpack="6.2", trt="10.4")
+    assert EngineFilenameSchema.matches_host(filename, host_mismatch_trt) is False
+
+
+def test_ac5_precision_enum_strictness() -> None:
+    with pytest.raises(EngineFilenameSchemaError, match=r"precision"):
+        EngineFilenameSchema.build("ultravpr", 87, "6.2", "10.3", "bf16")
+
+
+def test_ac6_model_name_character_set_rejection() -> None:
+    with pytest.raises(EngineFilenameSchemaError, match=r"a-z0-9_"):
+        EngineFilenameSchema.build("UltraVPR", 87, "6.2", "10.3", "fp16")
+
+
+def test_ac7_reserved_separator_collision_rejected() -> None:
+    with pytest.raises(EngineFilenameSchemaError, match=r"__"):
+        EngineFilenameSchema.build("ultra__vpr", 87, "6.2", "10.3", "fp16")
+
+
+def test_ac8_three_segment_version_rejected() -> None:
+    with pytest.raises(EngineFilenameSchemaError, match=r"major.*minor"):
+        EngineFilenameSchema.build("ultravpr", 87, "6.2.1", "10.3", "fp16")
+
+
+def test_ac9_parse_rejects_malformed_filename() -> None:
+    with pytest.raises(EngineFilenameSchemaError):
+        EngineFilenameSchema.parse("not_an_engine_file.engine")
+
+
+def test_ac10_parse_requires_engine_suffix() -> None:
+    with pytest.raises(EngineFilenameSchemaError, match=r"\.engine"):
+        EngineFilenameSchema.parse("ultravpr__sm87_jp6.2_trt10.3_fp16")
+
+
+def test_ac11_no_upward_imports_to_components() -> None:
+    module_path = (
+        Path(__file__).resolve().parents[2]
+        / "src"
+        / "gps_denied_onboard"
+        / "helpers"
+        / "engine_filename_schema.py"
+    )
+    tree = ast.parse(module_path.read_text(encoding="utf-8"))
+    bad: list[str] = []
+    for node in ast.walk(tree):
+        if isinstance(node, ast.ImportFrom) and node.module:
+            if node.module.startswith("gps_denied_onboard.components"):
+                bad.append(node.module)
+        elif isinstance(node, ast.Import):
+            for alias in node.names:
+                if alias.name.startswith("gps_denied_onboard.components"):
+                    bad.append(alias.name)
+    assert not bad, f"engine_filename_schema must not import components.*; found: {bad}"