build: the libavr pin advances past phase 6

The renames land (interrupt_guard, consume_reset_cause, set_duty), the
sampler binds its input in the new converter shape (the input pack plus
in<>::start() as free-running's one kick), and the console states
.allow_baud_error = true for the 115200-at-16-MHz this board has always
spoken - the receiver-tolerance table libavr now enforces is stricter
than the rate's own +2.1 %. The loader probe reads through
avr::flash_load instead of raw pgmspace, the terminal's line buffer is
std::array with backspace and delete named, the tree is reformatted
under InsertBraces, and the sources are ASCII.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

test/CMakeLists.txt

@@ -1,6 +1,6 @@
 # The board has no reset line and no programming header, so the loader-entry
 # route in the emitted image is the only thing standing between a firmware change
-# and an unreflashable board. It has been wrong before — see the script.
+# and an unreflashable board. It has been wrong before - see the script.
 find_package(Python3 COMPONENTS Interpreter)
 if(Python3_FOUND)
 	add_test(NAME fantemp.reachability
@@ -8,5 +8,5 @@ if(Python3_FOUND)
 	                 --objdump ${CMAKE_OBJDUMP} --elf $<TARGET_FILE:fantemp>
 	                 --image $<TARGET_FILE_DIR:fantemp>/fantemp.bin)
 else()
-	message(STATUS "Python not found — the reachability check is skipped")
+	message(STATUS "Python not found - the reachability check is skipped")
 endif()

test/check_reachability.py

@@ -3,7 +3,7 @@
 
 This board has no reset line and no programming header. The single route to the
 bootloader is the running firmware's `bootloader` command, so a firmware that
-gets that route wrong is a board that cannot be reflashed — and the failure is
+gets that route wrong is a board that cannot be reflashed - and the failure is
 silent, because everything else still works.
 
 It has been wrong before. The firmware this one replaces probed and jumped to
@@ -15,7 +15,7 @@ hardware, which is what this replaces.
 Three properties, all read out of the disassembly rather than the source:
 
 1. The image ends below the boot section. `hfuse d4` puts that at 0x7c00, so an
-   application reaching into it would be overwritten by the loader — or worse,
+   application reaching into it would be overwritten by the loader - or worse,
    executed at reset, since BOOTRST points there.
 2. The hand-over targets the loader base. A word address of 0x3f00 is byte
    0x7e00; anything else is the 0x7800 bug again.
@@ -60,7 +60,7 @@ def main() -> int:
     text = subprocess.run([args.objdump, "-d", str(args.elf)],
                           capture_output=True, text=True, check=True).stdout
 
-    # The address the hand-over actually targets, read at its call sites — not
+    # The address the hand-over actually targets, read at its call sites - not
     # "does the image contain this byte somewhere", which proves nothing: 0x3f is
     # an ordinary constant that appears in the curve tables, so a check like that
     # passes just as happily on the 0x7800 bug it is supposed to catch.
@@ -83,7 +83,7 @@ def main() -> int:
 
     want = LOADER_BASE // 2
     if not sites:
-        failures.append("no call to bootloader::call with a loaded target — the "
+        failures.append("no call to bootloader::call with a loaded target - the "
                         "hand-over could not be read out of the image")
     elif wrong := [a for a in sites if a != want]:
         failures.append(f"the hand-over targets word {[hex(a) for a in wrong]} "
@@ -95,13 +95,13 @@ def main() -> int:
 
     # An icall/ijmp has to exist for that address to be jumped to indirectly.
     if not re.search(r"\b(icall|ijmp)\b", text):
-        failures.append("no icall/ijmp — the hand-over cannot reach across flash")
+        failures.append("no icall/ijmp - the hand-over cannot reach across flash")
     else:
         print("  ok    an indirect call exists (a relative one cannot reach)")
 
     # What actually reaches WDTCSR, not what the image happens to load somewhere.
     # A timed disable writes WDCE|WDE (0x18) and then zero. Arming writes WDE
-    # *without* WDCE — including 0x08, a 16 ms timeout with every prescaler bit
+    # *without* WDCE - including 0x08, a 16 ms timeout with every prescaler bit
     # clear, which is precisely what the legacy route used and is why this cannot
     # be a check for "a prescaler is present".
     WDCE, WDE = 0x10, 0x08
@@ -114,14 +114,14 @@ def main() -> int:
             values.append(0 if reg == "r1" else held.get(reg))
     armed = [v for v in values if v is not None and (v & WDE) and not (v & WDCE)]
     if armed:
-        failures.append(f"WDTCSR is written {[hex(v) for v in armed]} — WDE without "
+        failures.append(f"WDTCSR is written {[hex(v) for v in armed]} - WDE without "
                         f"WDCE is arming the watchdog, and a reset-based hand-over "
                         f"opens no pureboot window")
     elif not values:
         print("  ok    the watchdog is never written")
     else:
         print(f"  ok    WDTCSR writes are {[hex(v) if v is not None else '?' for v in values]}"
-              f" — unlock and clear, never an arm")
+              f" - unlock and clear, never an arm")
 
     for line in failures:
         print(f"  FAIL  {line}")