fix: trust the probe for over-budget images; TIFF allowance

Review of the image wave (with empirical reproduction against the
vendored image 0.25) found the budget contract did not hold across
formats: the decoder's Limits reserve checks NATIVE bytes-per-pixel,
so a grayscale/RGB JPEG/PNG/BMP over the RGBA budget decoded anyway
and into_rgba8() then ballooned to up to 4x it — the tab death the
budgets exist to prevent. The probed dimensions already prove an
OverBudget image cannot fit, so it is now refused without decoding,
removing all dependence on per-decoder limit fidelity.

Conversely, image's TIFF codec stacks ~3x scratch buffers on top of
the reserve, so an in-budget TIFF (the flagship GIS scenario) was
refused with a self-contradictory note ('400 MB, over the 512 MB
limit'); the decoder allowance for TIFF is now 3x while tier math
stays on the real budget.

Also: the refusal message saturates instead of overflowing on crafted
headers, the image pick only matches the refusal note naming ITS file
(peek, not drain — other references' notes survive for their own
drains), and the Georgian Supplement range ends at U+2D2F (U+2D30.. is
Tifinagh, which ships no font).

(cherry picked from commit 58d3789bcf)

Ported onto main (#1717 review): the build-web.sh wrapper and its
pages/README/Trunk wiring stay out — it works around a local Windows
trunk dist lock; the Linux Pages build is unaffected.

src/io/mod.rs

@@ -2040,8 +2040,13 @@ pub async fn pick_image_file() -> Result<(PathBuf, u32, u32), String> {
     let decoded = crate::scene::model::image_model::resolve_image(&reference).ok_or_else(|| {
         // An over-budget decode refusal explains itself (dims + limit);
         // anything else stays the generic unsupported/corrupt message.
-        crate::scene::model::image_model::take_decode_refusals()
-            .pop()
+        // Only a note naming THIS pick explains its failure; the queue may
+        // also hold refusals queued by concurrent re-resolution of other
+        // references, which must survive for their own drains.
+        crate::scene::model::image_model::decode_refusals()
+            .iter()
+            .find(|note| note.contains(short.as_str()))
+            .cloned()
             .unwrap_or_else(|| format!("Unsupported or corrupt image \"{short}\""))
     })?;
     // Entity sizing truth: the file's ORIGINAL pixel dimensions, not the