Rename neural experiments to descriptive paths (drop N* codes)

configs/neural/{N0,N1,N2,N5}.yaml -> {bridge,collapse,grounding,architectures}.yaml,
results dirs likewise. Updated experiment/output.dir fields, comments/docstrings, and
docs; regenerated the four result manifests (now carrying the real git commit). No
functional path resolution referenced the codes (the Makefile globs configs/neural/*.yaml
and tests use inline configs), so nothing breaks. 92 tests green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

results/grounding/resolved_config.yaml

@@ -0,0 +1,305 @@
+experiment: grounding_phase_boundary
+seed: 20260704
+n_replicates: 5
+source_config:
+  experiment: grounding_phase_boundary
+  kind: gen_lineage
+  seed: 20260704
+  n_replicates: 5
+  generations: 30
+  synthetic:
+    K: 256
+    R: 1
+    tail: zipf
+    zipf_s: 1.3
+    tail_frac: 0.5
+    tail_threshold: 0.001
+    init: truth
+    style_len: 3
+    style_vocab: 5
+    id_base: 2
+  model:
+    kind: rnn
+    hidden: 128
+    embed: 24
+    epochs: 25
+    lr: 0.002
+    batch_size: 256
+    n_eval: 12000
+  dynamics:
+    n: 200
+    grounding:
+      m: 0
+      policy: proportional
+    remint:
+      enabled: false
+      period: null
+      H_gate: null
+  metrics:
+    kl_floor: 1.0e-09
+    support_eps: 1.0e-09
+  sweep:
+  - param: g
+    values:
+    - 0.0
+    - 0.005
+    - 0.01
+    - 0.02
+    - 0.05
+    - 0.1
+    - 0.2
+  output:
+    dir: results/grounding
+grid:
+- label:
+    g: 0.0
+    m: 0
+  neural_cfg:
+    synthetic:
+      K: 256
+      R: 1
+      tail: zipf
+      zipf_s: 1.3
+      tail_frac: 0.5
+      tail_threshold: 0.001
+      init: truth
+      style_len: 3
+      style_vocab: 5
+      id_base: 2
+    model:
+      kind: rnn
+      hidden: 128
+      embed: 24
+      epochs: 25
+      lr: 0.002
+      batch_size: 256
+      n_eval: 12000
+    dynamics:
+      n: 200
+      grounding:
+        m: 0
+        policy: proportional
+      remint:
+        enabled: false
+        period: null
+        H_gate: null
+    generations: 30
+    metrics:
+      kl_floor: 1.0e-09
+      support_eps: 1.0e-09
+- label:
+    g: 0.005
+    m: 1
+  neural_cfg:
+    synthetic:
+      K: 256
+      R: 1
+      tail: zipf
+      zipf_s: 1.3
+      tail_frac: 0.5
+      tail_threshold: 0.001
+      init: truth
+      style_len: 3
+      style_vocab: 5
+      id_base: 2
+    model:
+      kind: rnn
+      hidden: 128
+      embed: 24
+      epochs: 25
+      lr: 0.002
+      batch_size: 256
+      n_eval: 12000
+    dynamics:
+      n: 200
+      grounding:
+        m: 1
+        policy: proportional
+      remint:
+        enabled: false
+        period: null
+        H_gate: null
+    generations: 30
+    metrics:
+      kl_floor: 1.0e-09
+      support_eps: 1.0e-09
+- label:
+    g: 0.01
+    m: 2
+  neural_cfg:
+    synthetic:
+      K: 256
+      R: 1
+      tail: zipf
+      zipf_s: 1.3
+      tail_frac: 0.5
+      tail_threshold: 0.001
+      init: truth
+      style_len: 3
+      style_vocab: 5
+      id_base: 2
+    model:
+      kind: rnn
+      hidden: 128
+      embed: 24
+      epochs: 25
+      lr: 0.002
+      batch_size: 256
+      n_eval: 12000
+    dynamics:
+      n: 200
+      grounding:
+        m: 2
+        policy: proportional
+      remint:
+        enabled: false
+        period: null
+        H_gate: null
+    generations: 30
+    metrics:
+      kl_floor: 1.0e-09
+      support_eps: 1.0e-09
+- label:
+    g: 0.02
+    m: 4
+  neural_cfg:
+    synthetic:
+      K: 256
+      R: 1
+      tail: zipf
+      zipf_s: 1.3
+      tail_frac: 0.5
+      tail_threshold: 0.001
+      init: truth
+      style_len: 3
+      style_vocab: 5
+      id_base: 2
+    model:
+      kind: rnn
+      hidden: 128
+      embed: 24
+      epochs: 25
+      lr: 0.002
+      batch_size: 256
+      n_eval: 12000
+    dynamics:
+      n: 200
+      grounding:
+        m: 4
+        policy: proportional
+      remint:
+        enabled: false
+        period: null
+        H_gate: null
+    generations: 30
+    metrics:
+      kl_floor: 1.0e-09
+      support_eps: 1.0e-09
+- label:
+    g: 0.05
+    m: 11
+  neural_cfg:
+    synthetic:
+      K: 256
+      R: 1
+      tail: zipf
+      zipf_s: 1.3
+      tail_frac: 0.5
+      tail_threshold: 0.001
+      init: truth
+      style_len: 3
+      style_vocab: 5
+      id_base: 2
+    model:
+      kind: rnn
+      hidden: 128
+      embed: 24
+      epochs: 25
+      lr: 0.002
+      batch_size: 256
+      n_eval: 12000
+    dynamics:
+      n: 200
+      grounding:
+        m: 11
+        policy: proportional
+      remint:
+        enabled: false
+        period: null
+        H_gate: null
+    generations: 30
+    metrics:
+      kl_floor: 1.0e-09
+      support_eps: 1.0e-09
+- label:
+    g: 0.1
+    m: 22
+  neural_cfg:
+    synthetic:
+      K: 256
+      R: 1
+      tail: zipf
+      zipf_s: 1.3
+      tail_frac: 0.5
+      tail_threshold: 0.001
+      init: truth
+      style_len: 3
+      style_vocab: 5
+      id_base: 2
+    model:
+      kind: rnn
+      hidden: 128
+      embed: 24
+      epochs: 25
+      lr: 0.002
+      batch_size: 256
+      n_eval: 12000
+    dynamics:
+      n: 200
+      grounding:
+        m: 22
+        policy: proportional
+      remint:
+        enabled: false
+        period: null
+        H_gate: null
+    generations: 30
+    metrics:
+      kl_floor: 1.0e-09
+      support_eps: 1.0e-09
+- label:
+    g: 0.2
+    m: 50
+  neural_cfg:
+    synthetic:
+      K: 256
+      R: 1
+      tail: zipf
+      zipf_s: 1.3
+      tail_frac: 0.5
+      tail_threshold: 0.001
+      init: truth
+      style_len: 3
+      style_vocab: 5
+      id_base: 2
+    model:
+      kind: rnn
+      hidden: 128
+      embed: 24
+      epochs: 25
+      lr: 0.002
+      batch_size: 256
+      n_eval: 12000
+    dynamics:
+      n: 200
+      grounding:
+        m: 50
+        policy: proportional
+      remint:
+        enabled: false
+        period: null
+        H_gate: null
+    generations: 30
+    metrics:
+      kl_floor: 1.0e-09
+      support_eps: 1.0e-09