Add tests, server, resume training, and project cleanup

- Add 57 unit tests covering generators, models, and pipeline components
- Implement FastAPI HTTP service (server.py) with POST /solve and GET /health
- Add checkpoint resume (断点续训) to both CTC and regression training utils
- Fix device mismatch bug in CTC training (targets/input_lengths on GPU)
- Add pytest dev dependency to pyproject.toml
- Update .gitignore with data/solver/, data/real/, *.log
- Remove PyCharm template main.py
- Update training/__init__.py docs for solver training scripts

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tests/test_pipeline.py

@@ -0,0 +1,176 @@
+"""
+测试推理流水线组件。
+
+- math_eval: 加减乘除正确性 + 异常输入
+- CTC greedy decode (构造 logits)
+- SlideSolver (合成图 → OpenCV 检测)
+- generate_slide_track 轨迹合理性
+"""
+
+import math
+
+import numpy as np
+import pytest
+
+from inference.math_eval import eval_captcha_math
+from inference.pipeline import CaptchaPipeline
+
+
+# ============================================================
+# math_eval 测试
+# ============================================================
+class TestMathEval:
+    def test_addition(self):
+        assert eval_captcha_math("3+8=?") == "11"
+        assert eval_captcha_math("12+5") == "17"
+        assert eval_captcha_math("0+0=?") == "0"
+
+    def test_subtraction(self):
+        assert eval_captcha_math("15-7=?") == "8"
+        assert eval_captcha_math("20-20") == "0"
+
+    def test_multiplication(self):
+        assert eval_captcha_math("12×3=?") == "36"
+        assert eval_captcha_math("5*4") == "20"
+        assert eval_captcha_math("6x7") == "42"
+        assert eval_captcha_math("6X7") == "42"
+
+    def test_division(self):
+        assert eval_captcha_math("20÷4=?") == "5"
+        assert eval_captcha_math("9÷3") == "3"
+
+    def test_division_by_zero(self):
+        with pytest.raises(ValueError, match="除数为零"):
+            eval_captcha_math("5÷0=?")
+
+    def test_invalid_expression(self):
+        with pytest.raises(ValueError, match="无法解析"):
+            eval_captcha_math("abc")
+
+    def test_with_spaces(self):
+        assert eval_captcha_math("3 + 8 = ?") == "11"
+
+
+# ============================================================
+# CTC greedy decode 测试
+# ============================================================
+class TestCTCGreedyDecode:
+    """Test the static _ctc_greedy_decode method from CaptchaPipeline."""
+
+    def test_simple_decode(self):
+        chars = "ABC"  # index 0=blank, 1=A, 2=B, 3=C
+        T = 6
+        C = 4  # blank + 3 chars
+        logits = np.full((T, 1, C), -10.0, dtype=np.float32)
+        # Spell out "AB": A, A, blank, B, B, B
+        logits[0, 0, 1] = 10.0  # A
+        logits[1, 0, 1] = 10.0  # A (dup, collapsed)
+        logits[2, 0, 0] = 10.0  # blank
+        logits[3, 0, 2] = 10.0  # B
+        logits[4, 0, 2] = 10.0  # B (dup)
+        logits[5, 0, 2] = 10.0  # B (dup)
+        result = CaptchaPipeline._ctc_greedy_decode(logits, chars)
+        assert result == "AB"
+
+    def test_all_blank(self):
+        chars = "ABC"
+        T = 5
+        C = 4
+        logits = np.full((T, 1, C), -10.0, dtype=np.float32)
+        for t in range(T):
+            logits[t, 0, 0] = 10.0
+        result = CaptchaPipeline._ctc_greedy_decode(logits, chars)
+        assert result == ""
+
+    def test_repeated_chars_with_blank_separator(self):
+        chars = "ABC"
+        T = 5
+        C = 4
+        logits = np.full((T, 1, C), -10.0, dtype=np.float32)
+        # Spell "AA": A, blank, A, blank, blank
+        logits[0, 0, 1] = 10.0  # A
+        logits[1, 0, 0] = 10.0  # blank
+        logits[2, 0, 1] = 10.0  # A
+        logits[3, 0, 0] = 10.0  # blank
+        logits[4, 0, 0] = 10.0  # blank
+        result = CaptchaPipeline._ctc_greedy_decode(logits, chars)
+        assert result == "AA"
+
+
+# ============================================================
+# SlideSolver 测试
+# ============================================================
+class TestSlideSolver:
+    def test_solve_with_synthetic_image(self):
+        """Generate a synthetic slide image and verify the solver detects a gap."""
+        try:
+            import cv2
+        except ImportError:
+            pytest.skip("OpenCV not installed")
+
+        from generators.slide_gen import SlideDataGenerator
+        from solvers.slide_solver import SlideSolver
+
+        gen = SlideDataGenerator(seed=42)
+        img, label = gen.generate()
+        expected_gap_x = int(label)
+
+        solver = SlideSolver()
+        result = solver.solve(img)
+
+        assert "gap_x" in result
+        assert "gap_x_percent" in result
+        assert "confidence" in result
+        assert "method" in result
+        assert isinstance(result["gap_x"], int)
+        assert 0.0 <= result["gap_x_percent"] <= 1.0
+
+
+# ============================================================
+# generate_slide_track 测试
+# ============================================================
+class TestSlideTrack:
+    def test_track_basic(self):
+        from utils.slide_utils import generate_slide_track
+
+        track = generate_slide_track(100, seed=42)
+        assert isinstance(track, list)
+        assert len(track) >= 10
+
+    def test_track_point_structure(self):
+        from utils.slide_utils import generate_slide_track
+
+        track = generate_slide_track(150, seed=0)
+        for pt in track:
+            assert "x" in pt
+            assert "y" in pt
+            assert "t" in pt
+
+    def test_track_starts_at_origin(self):
+        from utils.slide_utils import generate_slide_track
+
+        track = generate_slide_track(100, seed=1)
+        assert track[0]["x"] == 0.0 or abs(track[0]["x"]) < 1e-6
+
+    def test_track_ends_near_distance(self):
+        from utils.slide_utils import generate_slide_track
+
+        distance = 120
+        track = generate_slide_track(distance, seed=2)
+        final_x = track[-1]["x"]
+        assert abs(final_x - distance) < 1.0, f"final x={final_x}, expected ~{distance}"
+
+    def test_track_time_increases(self):
+        from utils.slide_utils import generate_slide_track
+
+        track = generate_slide_track(100, seed=3)
+        for i in range(1, len(track)):
+            assert track[i]["t"] >= track[i - 1]["t"]
+
+    def test_track_y_has_jitter(self):
+        from utils.slide_utils import generate_slide_track
+
+        track = generate_slide_track(200, seed=4)
+        y_vals = [pt["y"] for pt in track]
+        # At least some y values should be non-zero (jitter)
+        assert any(abs(y) > 0 for y in y_vals)