Naming, layout and comments: descriptive full-word names, one item per line in wrapped calls and literals, and doc comments on exported names

Short and single-letter names in application code become full words (tests
keep theirs). Wrapped calls, signatures and composite literals put one item
per line, and one-line function bodies are expanded. Exported names and
groups of constants get doc comments, and comments refer to the renamed
identifiers.

internal/config/config.go

@@ -62,8 +62,8 @@ func (c *JobSearchConfig) SetValue(key string, value any) error {
 // Unknown keys are skipped; invalid values are logged and ignored.
 func LoadFromViper(conf *JobSearchConfig) {
 	keys := viper.AllKeys()
-	for idx := range keys {
-		key := keys[idx]
+	for i := range keys {
+		key := keys[i]
 		keyType, _ := conf.TypeOf(key)
 		if keyType == reflect.Invalid {
 			continue
@@ -94,15 +94,15 @@ func viperValue(key string, kind reflect.Kind) (value any, ok bool) {
 		// SetValue to split on commas; GetStringSlice would split it on
 		// spaces. A list of objects (a list of sections) is passed on as it
 		// is, as GetStringSlice would flatten it.
-		switch v := viper.Get(key).(type) {
+		switch value := viper.Get(key).(type) {
 		case string:
-			return v, true
+			return value, true
 		case []map[string]any: // as LoadToViper sets it
-			return v, true
+			return value, true
 		case []any:
-			if len(v) > 0 {
-				if _, ok := v[0].(map[string]any); ok {
-					return v, true
+			if len(value) > 0 {
+				if _, ok := value[0].(map[string]any); ok {
+					return value, true
 				}
 			}
 		}
@@ -121,26 +121,26 @@ func LoadToViper(conf JobSearchConfig) {
 
 // String formats the configuration one "key = value <type>" line per key, with
 // dotted keys, sorted by key.
-func (conf JobSearchConfig) String() string {
-	var sb strings.Builder
-	flat := conf.Flatten()
-	for _, k := range slices.Sorted(maps.Keys(flat)) {
-		typ, _ := conf.TypeOf(k)
-		fmt.Fprint(&sb, k, " = ", flat[k], " <", typ, ">\n")
+func (c JobSearchConfig) String() string {
+	var builder strings.Builder
+	flat := c.Flatten()
+	for _, key := range slices.Sorted(maps.Keys(flat)) {
+		kind, _ := c.TypeOf(key)
+		fmt.Fprint(&builder, key, " = ", flat[key], " <", kind, ">\n")
 	}
-	return sb.String()
+	return builder.String()
 }
 
 // JSON formats the configuration as indented JSON.
-func (conf JobSearchConfig) JSON() string {
-	confMap := conf.Map()
+func (c JobSearchConfig) JSON() string {
+	confMap := c.Map()
 	jbytes, _ := json.MarshalIndent(confMap, "", "  ")
 	return string(jbytes)
 }
 
 // YAML formats the configuration as YAML.
-func (conf JobSearchConfig) YAML() string {
-	confMap := conf.Map()
+func (c JobSearchConfig) YAML() string {
+	confMap := c.Map()
 	ybytes, _ := yaml.Marshal(confMap)
 	return string(ybytes)
 }