feat(pyproject): release v1.7.0 — Python pyproject.toml version bump

Add internal/pyproject package with ReadVersion and WriteVersion for
pyproject.toml files. Reads [project].version (PEP 621) first, then
falls back to [tool.poetry].version. Section boundaries are detected
via TOML's rule that headers always start at the beginning of a line
(\n[ pattern), so inline arrays with [ characters don't interfere.

Config follows the established multi-value pattern:
- python.pyproject_toml: single path (opt-in, no default)
- python.pyproject_tomls: list for monorepos (overrides single)
- --pyproject flag overrides pyproject_toml and clears pyproject_tomls

100% per-package statement coverage maintained across all 14 packages;
FuzzReadVersion and FuzzWriteVersion added per fuzzing guidelines.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/pyproject/pyproject.go

@@ -0,0 +1,74 @@
+package pyproject
+
+import (
+	"fmt"
+	"os"
+	"regexp"
+)
+
+// sectionRe matches a TOML section from its header to the next header (or end of file).
+// TOML section headers always appear at the start of a line, so \n[ is a reliable boundary.
+var (
+	projectSectionRe = regexp.MustCompile(`(?s)\[project\].*?(?:\n\[|\z)`)
+	poetrySectionRe  = regexp.MustCompile(`(?s)\[tool\.poetry\].*?(?:\n\[|\z)`)
+)
+
+// versionLineRe matches version = "x.y.z" on its own line inside a section.
+var versionLineRe = regexp.MustCompile(`(?m)^version\s*=\s*"([^"]+)"`)
+
+// ReadVersion returns the project version from a pyproject.toml file.
+// It checks [project] (PEP 621) first, then [tool.poetry] (Poetry).
+func ReadVersion(path string) (string, error) {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return "", fmt.Errorf("read %s: %w", path, err)
+	}
+	content := string(data)
+	for _, sectionRe := range []*regexp.Regexp{projectSectionRe, poetrySectionRe} {
+		section := sectionRe.FindString(content)
+		if section == "" {
+			continue
+		}
+		m := versionLineRe.FindStringSubmatch(section)
+		if m != nil {
+			return m[1], nil
+		}
+	}
+	return "", fmt.Errorf("no version found in %s", path)
+}
+
+// WriteVersion replaces the project version in a pyproject.toml file in-place.
+// oldVersion must match what ReadVersion returned.
+func WriteVersion(path, oldVersion, newVersion string) error {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return fmt.Errorf("read %s: %w", path, err)
+	}
+	updated, ok := replaceVersion(string(data), oldVersion, newVersion)
+	if !ok {
+		return fmt.Errorf("version %q not found in %s", oldVersion, path)
+	}
+	return os.WriteFile(path, []byte(updated), 0644)
+}
+
+// replaceVersion finds and replaces the version in the first [project] or [tool.poetry]
+// section that contains it. Returns the updated content and true on success.
+// regexp.QuoteMeta is used so version strings with dots or specials are safe.
+func replaceVersion(content, oldVersion, newVersion string) (string, bool) {
+	re := regexp.MustCompile(`(?m)^(version\s*=\s*)"` + regexp.QuoteMeta(oldVersion) + `"`)
+	for _, sectionRe := range []*regexp.Regexp{projectSectionRe, poetrySectionRe} {
+		loc := sectionRe.FindStringIndex(content)
+		if loc == nil {
+			continue
+		}
+		section := content[loc[0]:loc[1]]
+		m := re.FindStringSubmatchIndex(section)
+		if m == nil {
+			continue
+		}
+		// m[0]:m[1] = full match; m[2]:m[3] = group 1 (prefix "version = ")
+		newSection := section[:m[0]] + section[m[2]:m[3]] + `"` + newVersion + `"` + section[m[1]:]
+		return content[:loc[0]] + newSection + content[loc[1]:], true
+	}
+	return content, false
+}