chore: adopt engineering standard v1.0.0

Adopt the org engineering standard (its-consulting/standards @ v1.0.0).

Adds baseline governance/CI/policy files rendered from the standard's
templates and pins .standards-version=1.0.0. Vendored OPA/Rego policies
under .standards/policies/ so CI runs the gate locally (no cross-repo dep).
Placeholders ({{ORG}}/{{REPO}}/{{OWNER_HANDLE}}/{{MAINTAINER_EMAIL}}) filled in.
Existing files that differ were left untouched by the adopter.

Automated rollout. Files created: 15.

.editorconfig

@@ -0,0 +1,29 @@
+# .editorconfig — rendered by adopt-standard.sh (verbatim; no placeholders).
+# Mirrors the standards repo's own root .editorconfig.
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+indent_style = space
+indent_size = 2
+
+[*.{sh,bash,bats}]
+indent_size = 2
+
+[*.rego]
+indent_size = 2
+
+[*.py]
+indent_size = 4
+
+[*.md]
+trim_trailing_whitespace = false  # markdown hard line breaks
+
+[Makefile]
+indent_style = tab
+
+[*.{ps1,psm1,bat,cmd}]
+end_of_line = crlf