feat: add bytecode module loader

Add unified module storage with lazy decoding:
- Module: owns or mmaps bytecode, provides section views
- Instruction/InstructionView: decoded instruction wrappers
- StringsView, SymbolsView, TypesView, etc.
- Update binary format documentation

Author: zharinov

Cargo.lock

@@ -21,6 +21,7 @@ rowan = "0.16.1"
 serde = { version = "1.0.228", features = ["derive"] }
 thiserror = "2.0.17"
 arborium-tree-sitter = "2.3.2"
+memmap2 = "0.9"
 plotnik-core = { version = "0.1", path = "../plotnik-core" }
 plotnik-langs = { version = "0.1", path = "../plotnik-langs", optional = true }
 
@@ -31,3 +32,4 @@ default = ["plotnik-langs"]
 insta = { version = "=1.45.1", features = ["yaml"] }
 indoc = "=2.0.7"
 serde_json = "=1.0.148"
+tempfile = "3"

crates/plotnik-lib/Cargo.toml

@@ -8,6 +8,7 @@ mod entrypoint;
 mod header;
 mod ids;
 mod instructions;
+mod module;
 mod nav;
 mod sections;
 mod type_meta;
@@ -21,19 +22,26 @@ pub use ids::{QTypeId, StepId, StringId};
 
 pub use header::Header;
 
-pub use nav::Nav;
-
 pub use sections::{FieldSymbol, NodeSymbol, Slice, TriviaEntry};
 
-pub use effects::{EffectOp, EffectOpcode};
-
 pub use entrypoint::Entrypoint;
 
 pub use type_meta::{TypeDef, TypeKind, TypeMember, TypeMetaHeader, TypeName};
 
+pub use nav::Nav;
+
+pub use effects::{EffectOp, EffectOpcode};
+
 pub use instructions::{
     Call, Match, MatchView, Opcode, Return, align_to_section, select_match_opcode,
 };
 
+pub use module::{
+    ByteStorage, EntrypointsView, Instruction, InstructionView, Module, ModuleError, StringsView,
+    SymbolsView, TriviaView, TypesView,
+};
+
 #[cfg(test)]
 mod instructions_tests;
+#[cfg(test)]
+mod module_tests;