⬆️ version bump to v4.5

- Update obioptions.Version from "Release 4.4.29" to "/v/ Release v5"
- Update version.txt from 4.29 → .30
(automated by Makefile)

autodoc/docmd/pkg/obikmer/varint.md

@@ -0,0 +1,33 @@
+# Variable-Length Integer Encoding/Decoding Utility
+
+This Go package (`obikmer`) provides efficient serialization of `uint64` integers using **protobuf-style variable-length encoding (varint)**.
+
+## Core Features
+
+- ✅ `EncodeVarint(io.Writer, uint64) (n int, err error)`  
+  Writes a `uint64` as a compact varint to any `io.Writer`. Uses **7 bits per byte**, with the MSB as a continuation flag. Max 10 bytes for `uint64`.
+
+- ✅ `DecodeVarint(io.Reader) (val uint64, err error)`  
+  Reads and decodes a varint from any `io.Reader`. Handles multi-byte sequences safely; returns error on malformed input or overflow (>70 bits).
+
+- ✅ `VarintLen(uint64) int`  
+  Computes the exact byte length required to encode a value *without* performing I/O — useful for buffer preallocation or size estimation.
+
+## Encoding Scheme
+
+- Each byte holds 7 bits of data; bit 8 (MSB) = `1` if more bytes follow, else `0`.
+- Example:  
+  - `0x7F` → `1 byte`: `0111_1111`  
+  - `0x80` → `2 bytes`: `1000_0000 0000_0001`
+
+## Use Cases
+
+- Network protocols & binary file formats requiring compact integer representation  
+- Serialization frameworks (e.g., custom protobuf-like codecs)  
+- Embedded systems or bandwidth-constrained environments where space efficiency matters
+
+## Design Notes
+
+- No external dependencies; uses only `io` from the standard library.  
+- Thread-safe *per call* (no shared state), but `io.Reader`/`Writer` concurrency must be handled externally.  
+- Compatible with standard protobuf varint format (e.g., interoperable with `encoding/binary` or gRPC).