feat(k-ui): first slice: App trait + run loop, builders (column/row/text/button), flex layout, theme tokens (Whimsy Dark), tiny-skia + fontdue render (Noto Sans Latin subset), keyboard focus ring; tally demo; manifest memory key (pm spawns with it)

crates/manifest/src/fields.rs

@@ -144,3 +144,32 @@ impl Accent {
         u32::from_str_radix(hex, 16).ok().map(Self)
     }
 }
+
+/// How much memory an app may use, in 4 KiB pages: written `"512 KiB"` or
+/// `"3 MiB"`, from 64 KiB to 16 MiB.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct Memory(u16);
+
+impl Memory {
+    /// What an app gets unless its manifest says more: enough for a small
+    /// command-line program.
+    pub const DEFAULT: Self = Self(128);
+    const MIN_PAGES: u32 = 16;
+    const MAX_PAGES: u32 = 4096;
+
+    pub fn parse(s: &str) -> Option<Self> {
+        let (n, unit) = s.split_once(' ')?;
+        let n: u32 = n.parse().ok()?;
+        let kib = match unit {
+            "KiB" => n,
+            "MiB" => n.checked_mul(1024)?,
+            _ => return None,
+        };
+        let pages = kib.div_ceil(4);
+        (kib % 4 == 0 && (Self::MIN_PAGES..=Self::MAX_PAGES).contains(&pages)).then_some(Self(pages as u16))
+    }
+
+    pub fn pages(&self) -> usize {
+        self.0 as usize
+    }
+}

crates/manifest/src/lib.rs

@@ -16,7 +16,7 @@ mod tests;
 
 pub use capability::{Capabilities, Capability};
 pub use decision::{Decision, MAX_TEXT as MAX_DECISION_TEXT};
-pub use fields::{Accent, AppId, Command, FileName, Text, Version};
+pub use fields::{Accent, AppId, Command, FileName, Memory, Text, Version};
 pub use manifest::Manifest;
 
 /// Why a manifest or decision was refused; `line` is 1-based.

crates/manifest/src/manifest.rs

@@ -2,7 +2,7 @@
 
 use crate::Error;
 use crate::capability::{Capabilities, Capability};
-use crate::fields::{Accent, AppId, Command, FileName, Text, Version};
+use crate::fields::{Accent, AppId, Command, FileName, Memory, Text, Version};
 use crate::toml::{self, Entry, Value};
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
@@ -15,6 +15,8 @@ pub struct Manifest {
     pub command: Command,
     pub author: Option<Text<64>>,
     pub icon: Option<FileName>,
+    /// How much memory it may use.
+    pub memory: Memory,
     /// Denied = not installed.
     pub required: Capabilities,
     /// The owner decides each.
@@ -32,6 +34,7 @@ struct Draft {
     command: Option<Command>,
     author: Option<Text<64>>,
     icon: Option<FileName>,
+    memory: Option<Memory>,
     required: Option<Capabilities>,
     optional: Option<Capabilities>,
     accent: Option<Accent>,
@@ -81,6 +84,7 @@ impl Draft {
             ("app", "command") => set(&mut self.command, s.and_then(Command::new), l),
             ("app", "author") => set(&mut self.author, s.and_then(Text::new), l),
             ("app", "icon") => set(&mut self.icon, s.and_then(FileName::new), l),
+            ("app", "memory") => set(&mut self.memory, s.and_then(Memory::parse), l),
             ("capabilities", "required") => {
                 set(&mut self.required, Some(capabilities(e.value, l)?), l)
             }
@@ -116,6 +120,7 @@ impl Manifest {
             command,
             author: d.author,
             icon: d.icon,
+            memory: d.memory.unwrap_or(Memory::DEFAULT),
             required,
             optional,
             accent: d.accent,

crates/manifest/src/tests.rs

@@ -239,3 +239,13 @@ fn every_capability_name_round_trips_and_fits_the_set() {
         all
     );
 }
+
+#[test]
+fn memory_is_in_kib_or_mib_within_bounds() {
+    use crate::Memory;
+    assert_eq!(Memory::parse("3 MiB").map(|m| m.pages()), Some(768));
+    assert_eq!(Memory::parse("512 KiB").map(|m| m.pages()), Some(128));
+    for bad in ["3MiB", "3 GiB", "17 MiB", "32 KiB", "6 KiB", "-1 MiB", "x MiB"] {
+        assert_eq!(Memory::parse(bad), None, "{bad}");
+    }
+}