chore: extract some minor changes from #18861 (#18866)

doing my usual thing of extracting no-brainer changes from a giant PR to
try and make it slightly less giant

packages/svelte/src/internal/client/dev/tracing.js

@@ -131,8 +131,10 @@ export function trace(label, fn) {
 }
 
 /**
- * @param {Value} source
+ * @template {Value} T
+ * @param {T} source
  * @param {string} label
+ * @returns {T}
  */
 export function tag(source, label) {
 	source.label = label;

packages/svelte/src/internal/client/dom/blocks/each.js

@@ -1,4 +1,4 @@
-/** @import { EachItem, EachOutroGroup, EachState, Effect, EffectNodes, MaybeSource, Source, TemplateNode, TransitionManager, Value } from '#client' */
+/** @import { EachItem, EachOutroGroup, EachState, Effect, EffectNodes, MaybeSource, TemplateNode, TransitionManager } from '#client' */
 /** @import { Batch } from '../../reactivity/batch.js'; */
 import {
 	EACH_INDEX_REACTIVE,
@@ -664,7 +664,7 @@ function reconcile(state, array, anchor, flags, get_key) {
  * @param {V} value
  * @param {unknown} key
  * @param {number} index
- * @param {(anchor: Node, item: V | Source<V>, index: number | Value<number>, collection: () => V[]) => void} render_fn
+ * @param {(anchor: Node, item: MaybeSource<V>, index: MaybeSource<number>, collection: () => V[]) => void} render_fn
  * @param {number} flags
  * @param {() => V[]} get_collection
  * @returns {EachItem}

packages/svelte/src/internal/client/reactivity/batch.js

@@ -1295,6 +1295,10 @@ export function eager(fn) {
 	let version = version_map.get(parent) ?? source(0);
 	version_map.set(parent, version);
 
+	if (DEV) {
+		version.label ??= '$state.eager version';
+	}
+
 	teardown(() => {
 		if (parent.f & DESTROYING) version_map.delete(parent);
 	});

packages/svelte/src/internal/client/reactivity/sources.js

@@ -46,7 +46,7 @@ import { set_signal_status, update_derived_status } from './status.js';
 /** @type {Set<Effect>} */
 export let eager_effects = new Set();
 
-/** @type {Map<Source, any>} */
+/** @type {Map<Value, any>} */
 export const old_values = new Map();
 
 /**
@@ -141,7 +141,7 @@ export function mutate(source, value) {
 
 /**
  * @template V
- * @param {Source<V>} source
+ * @param {Value<V>} source
  * @param {V} value
  * @param {boolean} [should_proxy]
  * @returns {V}
@@ -181,7 +181,7 @@ var count_deps = 0;
 
 /**
  * @template V
- * @param {Source<V>} source
+ * @param {Value<V>} source
  * @param {V} value
  * @param {Effect[] | null} [updated_during_traversal]
  * @returns {V}

packages/svelte/src/internal/client/runtime.js

@@ -93,7 +93,7 @@ export function set_active_effect(effect) {
 /**
  * When sources are created within a reaction, reading and writing
  * them within that reaction should not cause a re-run
- * @type {null | Set<Source>}
+ * @type {null | Set<Value>}
  */
 export let current_sources = null;
 
@@ -121,11 +121,11 @@ export let skipped_deps = 0;
 /**
  * Tracks writes that the effect it's executed in doesn't listen to yet,
  * so that the dependency can be added to the effect later on if it then reads it
- * @type {null | Source[]}
+ * @type {null | Value[]}
  */
 export let untracked_writes = null;
 
-/** @param {null | Source[]} value */
+/** @param {null | Value[]} value */
 export function set_untracked_writes(value) {
 	untracked_writes = value;
 }

packages/svelte/src/reactivity/date.js

@@ -1,4 +1,4 @@
-/** @import { Source } from '#client' */
+/** @import { Derived } from '#client' */
 import { derived } from '../internal/client/index.js';
 import { set, state } from '../internal/client/reactivity/sources.js';
 import { tag } from '../internal/client/dev/tracing.js';
@@ -42,7 +42,7 @@ var inited = false;
 export class SvelteDate extends Date {
 	#time = state(super.getTime());
 
-	/** @type {Map<keyof Date, Source<unknown>>} */
+	/** @type {Map<keyof Date, Derived<unknown>>} */
 	#deriveds = new Map();
 
 	#reaction = active_reaction;