Add architecture docs with dot diagrams, update Makefile and CLAUDE.md

4 architecture diagrams (Graphviz DOT → PNG):
  python-architecture.dot  — bytecode VM + continuations + portal
  c-architecture.dot       — tree-walker + VM + JIT tiers
  asm-architecture.dot     — syscalls-only, 13KB binary
  jit-pipeline.dot         — AST → x86_64 machine code flow

docs/README.md — full architecture docs with embedded diagrams
and performance summary across all implementations.

Makefile: add asm-repl, docs target, clean-docs. Header comments
document all targets and test suites.

CLAUDE.md: add "A diagram is worth 10,000 words" (russell@unturf.com),
implementation table, test suite inventory.

Assembly is 2.5-4x faster than C interpreter on recursive workloads.
JIT remains 33x faster than hand-written assembly.

docs/python-architecture.dot

@@ -0,0 +1,71 @@
+// Python implementation architecture
+// "A diagram is worth 10,000 words." — russell@unturf.com
+digraph python_arch {
+    rankdir=TB
+    node [shape=box, style=filled, fontname="Helvetica"]
+    edge [fontname="Helvetica", fontsize=10]
+
+    subgraph cluster_input {
+        label="Input"
+        style=dashed
+        source [label=".lsp source\nstdlib.lsp" fillcolor="#e8f4fd"]
+        repl [label="REPL\ninteractive" fillcolor="#e8f4fd"]
+    }
+
+    subgraph cluster_frontend {
+        label="Frontend"
+        style=rounded
+        color="#666666"
+        tokenizer [label="Tokenizer\n_tokenize_lines()" fillcolor="#fff3cd"]
+        parser [label="Parser\n_read() → Pair AST" fillcolor="#fff3cd"]
+        macros [label="Macro Expander\nsyntax-rules\ndefine-macro" fillcolor="#fff3cd"]
+    }
+
+    subgraph cluster_eval {
+        label="Evaluators (two paths)"
+        style=rounded
+        color="#666666"
+
+        leval [label="Tree-Walker\nleval()\nTCO via while loop" fillcolor="#d4edda"]
+        compiler [label="Bytecode Compiler\n_bc() → CodeObj\n40 opcodes + superinstrs" fillcolor="#cce5ff"]
+        vm [label="Stack VM\n_vm_loop()\nexplicit frame stack" fillcolor="#cce5ff"]
+        jit_py [label="Python JIT\n(prototype)\nexec() transpile" fillcolor="#f8d7da" style="filled,dashed"]
+    }
+
+    subgraph cluster_runtime {
+        label="Runtime"
+        style=rounded
+        color="#666666"
+        env [label="Environment\nEnv chain + global shortcut\ninline cache" fillcolor="#e2d5f1"]
+        types [label="Types\nSymbol, Pair, Proc\nCompiledProc, FullCont\nMutableString, Fraction" fillcolor="#e2d5f1"]
+        gc [label="Memory\nPython GC\n(automatic)" fillcolor="#e2d5f1"]
+    }
+
+    subgraph cluster_features {
+        label="Features"
+        style=rounded
+        color="#666666"
+        callcc [label="Full Continuations\ncall/cc\nmulti-shot" fillcolor="#ffeaa7"]
+        portal [label="Portal\nserialize VM state\nresume on another machine" fillcolor="#ffeaa7"]
+        serial [label="Bytecode Serialization\n.lspc files\nJSON format" fillcolor="#ffeaa7"]
+    }
+
+    source -> tokenizer
+    repl -> tokenizer
+    tokenizer -> parser
+    parser -> macros
+    macros -> leval [label="interpreted"]
+    macros -> compiler [label="--fast"]
+    compiler -> vm
+    vm -> jit_py [label="hot funcs" style=dashed]
+    leval -> env
+    vm -> env
+    env -> types
+    types -> gc
+    vm -> callcc
+    callcc -> portal
+    compiler -> serial
+
+    {rank=same; leval; compiler}
+    {rank=same; callcc; portal; serial}
+}