refact(comments): state the mechanism, not the incident

Every comment that invoked a 'law' (50 word-boundary sites across 28
tracked files) now states what is going on and why, in terms that
transfer to any project: gate twins drift until one side greenlights
what the other refuses; a tag re-points while a digest pins; a
restrictive engine behavior belongs to the runtime that imposed it and
must be re-tested, not inherited; a speculative head is tensors in the
file, not a flag; snapshot links dangle where the container resolves
them; exit 0 is a clean stop to systemd, so a self-exiting daemon on
on-failure goes dark reporting success. Event narratives and dates are
gone from these comments; the mechanics carry the argument.

Behavior-identical: bash -n, py_compile, yaml parse, full bats suite
408/408 green. One symbol rename rides along (stack script local
scale_law -> scale_contract, with its log text).

scripts/convert-swift15-w4dn8.sh

@@ -26,8 +26,8 @@ RECIPE=/home/dank/serverAppConfigs-swift15/scripts/recipes/qwen4exp-swift15-w4dn
 CALIB=/home/dank/corpora/calib
 OUT=/home/dank/models/rad/qwen4exp-swift15-w4dn8-i8-hc8m.rad
 LOG=/home/dank/logs/swift15_convert.log
-# gate_up ~37.6 + down ~18.8 + PLE 47.7 + trunk/embeddings/head ~10 GiB (all-w4 expert table;
-# the plugin's one-encoding law dropped the block-fp8 down tier -- see the recipe header).
+# gate_up ~37.6 + down ~18.8 + PLE 47.7 + trunk/embeddings/head ~10 GiB (all-w4 expert
+# table; one encoding per expert table rules out a block-fp8 down tier -- see the recipe header).
 MIN_MIB=${FRANK_SWIFT15_RAD_MIN_MIB:-108000}
 
 # Gate 1: inputs. A missing Gram directory converts UNCALIBRATED with a