v0.4.0

Added

• ADFS disc image support (read-only): beebtools now reads .adf
  (single-sided) and .adl (double-sided) ADFS disc images using the old-map
  small-directory ("Hugo") format. Supports ADFS-S (160K), ADFS-M (320K), and
  ADFS-L (640K) images. All read commands (cat, extract, search) work
  transparently with both DFS and ADFS images.

• ADFS write support: beebtools create, add, delete, and build
  commands now work with ADFS disc images (.adf, .adl). Format is detected
  from the file extension. Create supports ADFS-S (160K, 40-track .adf),
  ADFS-M (320K, 80-track .adf), and ADFS-L (640K, .adl). File paths use
  the ADFS hierarchical syntax (e.g. $.GAMES.ELITE). Build walks the source
  directory tree recursively, creating subdirectories as needed.

• createAdfsImage() library function: creates a blank ADFS disc image with
  valid free space map and root directory. Accepts format size, title, and boot
  option parameters.

• validateAdfsName() library function: validates ADFS filenames (1-10
  printable ASCII characters).

• buildAdfsImage() library function: assembles an ADFS disc image from a
  directory tree with .inf sidecars, including recursive subdirectory creation.

• openImage() format auto-detection dispatcher: detects DFS or ADFS from the
  file extension and delegates to the appropriate parser. Exported from the
  public API.

• ADFS library types exported from the public API: ADFSEntry, ADFSCatalogue,
  ADFSDirectory, ADFSFreeSpaceMap, ADFSImage, ADFSSide, ADFSError,
  ADFSFormatError, openAdfsImage.

• beebtools cat on ADFS images shows the full hierarchical directory tree with
  directory entries labelled as DIR. Column width adjusts dynamically for long
  ADFS path names.

• beebtools extract accepts ADFS full paths (e.g. $.GAMES.ELITE) as well as
  bare filenames. Bulk extraction (-a) creates nested filesystem directories
  matching the ADFS directory hierarchy. Directory entries are skipped.

• beebtools search works on ADFS images, searching all BASIC files across the
  entire directory tree.

• BBC BASIC II tokenizer (tokenize.py): converts LIST-style plain text back
  to tokenized binary - the inverse of the detokenizer. tokenize() and
  encodeLineRef() are exported from the public API.

• beebtools add --basic now auto-tokenizes plain-text BASIC files before adding
  them to a disc image, enabling a full detokenize-edit-retokenize workflow.

• --basic flag for beebtools add: sets BBC BASIC default addresses
  (load=0x1900, exec=0x8023) without needing to specify them manually.
  Explicit --load or --exec flags override the corresponding default
  with an informational note. Ignored with a warning when --inf is used.

Fixed

• DFS filename validation now rejects the characters . : " # * and space,
  matching the Acorn DFS disc format specification. Previously only the
  printable ASCII range was checked.

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