W60: Goto dialog parity — percent/offset/hex options

MC's goto dialog supports Line/Percent/Decimal offset/Hex offset
modes. TLC's goto prompt previously only accepted line numbers.

Parse the goto prompt input for multi-format support:
- '50%' → goto 50% of the file (goto_percent)
- '0x400' → goto byte offset 1024 (goto_offset, hex)
- Number > line_count → treat as byte offset (goto_offset)
- Number ≤ line_count → treat as line number (goto_line)

Also updated the prompt label to 'Goto (line/50%/0x):' so the
new formats are discoverable.

Added 1 unit test verifying 50% goto lands near line 50 in a
100-line file.

Tests: 1421 pass (was 1420), zero warnings.

local/recipes/tui/tlc/source/src/viewer/mod.rs

@@ -816,7 +816,7 @@ impl Viewer {
         let label = match self.prompt {
             Some(ViewerPrompt::Search) => " Search: ",
             Some(ViewerPrompt::SearchBackward) => " Search backward: ",
-            Some(ViewerPrompt::GotoLine) => " Goto line: ",
+            Some(ViewerPrompt::GotoLine) => " Goto (line/50%/0x): ",
             Some(ViewerPrompt::SaveBeforeQuit) => " Save before quit? (Y/N/Esc) ",
             None => return,
         };
@@ -1202,13 +1202,42 @@ impl Viewer {
                     }
                 }
                 ViewerPrompt::GotoLine => {
-                    if let Ok(n) = text.trim().parse::<u64>() {
-                        if n >= 1 {
-                            if let Ok(target) = self.goto_line(n) {
+                    let trimmed = text.trim();
+                    // Percent: "50%" → goto 50% of the file.
+                    if let Some(pct) = trimmed.strip_suffix('%') {
+                        if let Ok(n) = pct.parse::<u64>() {
+                            if n <= 100 {
+                                if let Ok(target) = self.goto_percent(n) {
+                                    self.cursor = target.offset;
+                                    self.top = target.line.saturating_sub(1);
+                                }
+                            }
+                        }
+                    // Hex offset: "0x400" → goto byte offset 1024.
+                    } else if trimmed.starts_with("0x") || trimmed.starts_with("0X") {
+                        if let Ok(off) = u64::from_str_radix(&trimmed[2..], 16) {
+                            if let Ok(target) = self.goto_offset(off) {
                                 self.cursor = target.offset;
                                 self.top = target.line.saturating_sub(1);
                             }
                         }
+                    // Decimal offset: plain number → goto byte offset
+                    // if it's larger than the file's line count, else
+                    // goto line.
+                    } else if let Ok(n) = trimmed.parse::<u64>() {
+                        if n >= 1 {
+                            if n > self.goto.line_count() {
+                                if let Ok(target) = self.goto_offset(n) {
+                                    self.cursor = target.offset;
+                                    self.top = target.line.saturating_sub(1);
+                                }
+                            } else {
+                                if let Ok(target) = self.goto_line(n) {
+                                    self.cursor = target.offset;
+                                    self.top = target.line.saturating_sub(1);
+                                }
+                            }
+                        }
                     }
                 }
                 ViewerPrompt::SaveBeforeQuit => {
@@ -1849,6 +1878,21 @@ mod tests {
         assert!(!v.ruler);
     }
 
+    #[test]
+    fn goto_accepts_percent_and_offset() {
+        // Use a 100-line file so 50% = line 50.
+        let lines: Vec<String> = (1..=100).map(|i| format!("line{i}")).collect();
+        let content = lines.join("\n");
+        let p = make_text("goto-fmt.txt", content.as_bytes());
+        let mut v = Viewer::open(&p).unwrap();
+        // Open goto prompt.
+        v.prompt = Some(ViewerPrompt::GotoLine);
+        v.prompt_input = "50%".to_string();
+        // Activate the prompt — the commit handler processes it.
+        v.handle_prompt_key(Key::ENTER);
+        assert!(v.top >= 49 && v.top <= 51, "50% should land near line 50, got top={}", v.top);
+    }
+
     fn k(c: char) -> Key {
         Key { code: c as u32, mods: crate::key::Modifiers::empty() }
     }