feat(cli): ludic deps - the module graph as the compiler resolved it

With LUDIC_DEPS=<file> the compiler records every reference the
visibility pass resolves (from module, to module) and every assignment
to another module's global. ludic deps prints the modules,
dependencies, largest cycle, cross writes and globals written from
outside, with --graph, --dot, --writes, --uses MOD, --check FILE and
--baseline FILE. Reseed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

examples/modules/tangle.ludic

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+# tangle.ludic — the program `ludic deps` is tested on: a and b use each other (the largest cycle is
+# 2), both use the leaf c (not counted), and a writes b's global b_count (one cross-module write).
+#
+# Running it prints:  4
+import "tangle/c"
+import "tangle/a"
+import "tangle/b"
+program Tangle {
+  entry {
+    print(a_run())
+  }
+}

examples/modules/tangle/a/index.ludic

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+# a/index.ludic - uses b, and writes b's global from outside it
+module a
+export function a_run() -> int {
+  b_count = b_count + 1
+  return b_run() + c_one()
+}
+export function a_two() -> int {
+  return 2
+}

examples/modules/tangle/b/index.ludic

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+# b/index.ludic - uses a back: a and b are a cycle
+module b
+export var b_count: int = 0
+export function b_run() -> int {
+  return a_two() + c_one()
+}

examples/modules/tangle/c/index.ludic

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+# c/index.ludic - uses nothing: a leaf, which the dependencies do not count
+module c
+export function c_one() -> int {
+  return 1
+}