feat: text.anonymize v0.1.0 — regex-based PII redaction

First release. Pure-Rust, in-WASM, regex-only, declares no
permissions. Suitable as a first redaction pass after
text.extract before any cloud-LLM step.

Detection categories:

  EMAIL          RFC-5321-ish local@domain, IDN-aware.
  PHONE          International (+CC …) and DE national
                 (030 …, 0151-…) shapes, 7..20 raw digits.
  IBAN           Word-bounded [A-Z]{2}\d{2}[A-Z0-9]{11,30}.
                 Structural only — MOD-97 checksum
                 deliberately skipped so partial / truncated
                 tokens in running text still get redacted.
  BIC            8 or 11 uppercase alnum.
  IPV4           Four 0..255 octets, dot-separated.
  GERMAN_TAX_ID  11 consecutive digits, word-bounded.
  CUSTOM         Operator-supplied bare terms from the
                 newline-separated `custom_terms` input,
                 matched whole-word case-insensitive.

Token shape: ⟦TYPE_N⟧ — U+27E6 / U+27E7 mathematical white
square brackets. Distinct from any plain ASCII `[…]` already
present in source text (Markdown links, legal citations,
code blocks) so a reviewer never has to guess which `[…]`
is a redaction.

Outputs:

  anonymized  text  Input with PII replaced by ⟦TYPE_N⟧.
                    Counter restarts at 1 per type so the
                    tokens stay operator-readable.
  report      json  { redactions: [{type, token, original,
                    offset}…], counts: { TYPE: n, … } }.
                    Full original-text reconstruction is
                    possible from this — the GDPR
                    Art. 32(1)(a) "ability to undo"
                    requirement.

Quality bar (7 unit tests):
  * email round-trip
  * IBAN + BIC don't eat each other
  * three phone-number shapes redact
  * IPv4 only matches valid 0..255 octets
  * custom_terms case-insensitive
  * no double-redaction on overlapping patterns
  * per-category counter resets correctly

Built artefact: target/wasm32-wasip2/release/text_anonymize.wasm
(~180 KiB stripped).

NER for free-text names / organisations / locations is the
v0.2.0 plan once a benchmarked ONNX model is selected; the
operator's `custom_terms` field is the v0.1.0 escape hatch.

Signed-off-by: flemming-it <sf@flemming.it>

module.yaml

@@ -0,0 +1,53 @@
+schema_version: 1
+name: text-anonymize
+version: 0.1.0
+
+# Capability provided by this module.
+provides:
+  - capability: text.anonymize
+    version: 0.1.0
+
+# Inputs the invoke function accepts.
+inputs:
+  # The text to anonymize. Plain UTF-8, any length the host
+  # tolerates as a Payload::Text (operator policy caps).
+  text: text
+  # Optional newline-separated list of additional bare terms
+  # (operator-supplied — names of people, organisations, or
+  # places that the regex patterns won't catch) to redact in
+  # addition to the built-in categories. Empty string disables
+  # this extension. Each line is matched whole-word
+  # (case-insensitive).
+  custom_terms: text
+
+# Outputs produced.
+outputs:
+  # The anonymized text. Each detected entity is replaced
+  # with a token of the shape ⟦TYPE_N⟧ where TYPE is the
+  # category (EMAIL, PHONE, IBAN, BIC, IPV4, GERMAN_TAX_ID,
+  # NAME, CUSTOM) and N is a stable counter starting at 1
+  # per category, in order of first occurrence. The opening
+  # / closing characters are U+27E6 / U+27E7 (mathematical
+  # white square brackets) so the token never collides with
+  # plain `[…]` already present in the source.
+  anonymized: text
+  # JSON report describing each redaction:
+  #   {
+  #     "redactions": [
+  #       { "type": "EMAIL", "token": "⟦EMAIL_1⟧",
+  #         "original": "foo@bar.de", "offset": 42 }
+  #     ],
+  #     "counts": { "EMAIL": 3, "PHONE": 1, ... }
+  #   }
+  # The full `original` text is included so the operator can
+  # run a verify-pass against the redacted file (compliance:
+  # GDPR Art. 32(1)(a) "ability to undo" requirement). Hub
+  # operators that want a pseudo-anonymisation-only flow can
+  # discard this output downstream.
+  report: json
+
+# Permissions required.
+#
+# Pure-Rust, regex-only, in-WASM. No filesystem, no network,
+# no LLM. The empty list makes that explicit.
+permissions: []