remove food from ambient energy forms, size solar sails to actual power needs

Biological Feed (food) was treated as an "ambient" energy source, so
range_fuel always reported the domain's ceiling regardless of how much
food was carried -- stopping to eat is a resupply, the same category as
refuelling a tank, not a genuinely external/inexhaustible source like
sun or wind. Removed "biological" from AMBIENT_ENERGY_FORMS; food now
uses the normal storage-mass-limited range formula like any fuel.

Solar Sail was still special-cased to a fixed footprint-derived mass
(100m^2 -> 5kg) regardless of what a domain's power/velocity target
actually needed -- the same "fixed reference instead of a requirement
floor" bug biological actuators had before last session's fix. Folded
it into the same general requirement-floor + joint-optimizer path:
declared footprint becomes a FLOOR (SAIL_AREAL_DENSITY_KG_PER_M2), not
a fixed value, so sail size scales with what's actually needed --
"enough panels to supply enough power for actuator impulse" is now
enforced the same way structural/mass-ceiling requirements already are,
instead of relying on a product-spec constant that happened to work or
not. No actuator type is special-cased for mass sizing anymore.

Confirmed the fix surfaces an honest result rather than hiding one: a
solar sail's declared 0.01 W/kg specific power can never reach
interplanetary_travel's 10 W/kg power_density floor at any sail size
(the ratio is capped by the sail's own power_density regardless of
scale), so it correctly still scores 0 there -- a real technology/domain
mismatch, not a sizing bug.

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

src/physcom_web/templates/results/_explore_result.html

@@ -1,8 +1,6 @@
 {% if explore_result is none %}
 <p class="empty">No free mass allocation to explore for this combination — its
-actuator's mass isn't a design choice (a footprint-derived quantity, like a
-radiation-pressure sail), or the platform has no declared mass ceiling to
-bound the sliders.</p>
+platform has no declared mass ceiling to bound the sliders.</p>
 {% else %}
 {% set r = explore_result %}
 <div class="optimize-summary">

src/physcom_web/templates/results/detail.html

@@ -155,7 +155,7 @@
       <output id="out_platform_mass">{{ "%.1f"|format(r.platform_mass) }}kg</output>
     </div>
     <div class="weight-slider-row">
-      <label for="actuator_mass">actuator (motor size, or operator count/size for muscle power)</label>
+      <label for="actuator_mass">actuator (motor/collector size, or operator count/size for muscle power)</label>
       <input type="range" min="{{ r.actuator_min }}" max="{{ r.actuator_slider_max }}" step="0.1"
              id="actuator_mass" name="actuator_mass" value="{{ r.actuator_mass }}"
              oninput="document.getElementById('out_actuator_mass').textContent = (+this.value).toFixed(1) + 'kg'">